Move browser accessibility code from chrome to content.

BUG=85932
TEST=none
Review URL: http://codereview.chromium.org/7233022

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@90265 0039d316-1c4b-4281-b951-d872f2087c98

20 files changed, 4483 insertions, 1 deletions

diff --git a/content/browser/accessibility/OWNERS b/content/browser/accessibility/OWNERS
new file mode 100644
index 0000000..ab8afa4
--- /dev/null
+++ b/content/browser/accessibility/OWNERS
@@ -0,0 +1,3 @@
+ctguil@chromium.org
+dmazzoni@chromium.org
+dtseng@chromium.org
diff --git a/content/browser/accessibility/browser_accessibility.cc b/content/browser/accessibility/browser_accessibility.cc
new file mode 100644
index 0000000..784bae0
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility.cc
@@ -0,0 +1,204 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/accessibility/browser_accessibility.h"
+
+#include "base/logging.h"
+#include "base/string_number_conversions.h"
+#include "content/browser/accessibility/browser_accessibility_manager.h"
+
+#if defined(OS_POSIX) && !defined(OS_MACOSX)
+// There's no OS-specific implementation of BrowserAccessibilityManager
+// on Unix, so just instantiate the base class.
+// static
+BrowserAccessibility* BrowserAccessibility::Create() {
+  return new BrowserAccessibility();
+}
+#endif
+
+BrowserAccessibility::BrowserAccessibility()
+    : manager_(NULL),
+      parent_(NULL),
+      child_id_(0),
+      index_in_parent_(0),
+      renderer_id_(0),
+      ref_count_(1),
+      role_(0),
+      state_(0),
+      instance_active_(false) {
+}
+
+BrowserAccessibility::~BrowserAccessibility() {
+}
+
+void BrowserAccessibility::DetachTree(
+    std::vector<BrowserAccessibility*>* nodes) {
+  nodes->push_back(this);
+  for (size_t i = 0; i < children_.size(); i++)
+    children_[i]->DetachTree(nodes);
+  children_.clear();
+  parent_ = NULL;
+}
+
+void BrowserAccessibility::Initialize(
+    BrowserAccessibilityManager* manager,
+    BrowserAccessibility* parent,
+    int32 child_id,
+    int32 index_in_parent,
+    const webkit_glue::WebAccessibility& src) {
+  manager_ = manager;
+  parent_ = parent;
+  child_id_ = child_id;
+  index_in_parent_ = index_in_parent;
+
+  renderer_id_ = src.id;
+  name_ = src.name;
+  value_ = src.value;
+  attributes_ = src.attributes;
+  html_attributes_ = src.html_attributes;
+  location_ = src.location;
+  role_ = src.role;
+  state_ = src.state;
+  indirect_child_ids_ = src.indirect_child_ids;
+  line_breaks_ = src.line_breaks;
+
+  Initialize();
+}
+
+void BrowserAccessibility::Initialize() {
+  instance_active_ = true;
+}
+
+void BrowserAccessibility::AddChild(BrowserAccessibility* child) {
+  children_.push_back(child);
+}
+
+void BrowserAccessibility::UpdateParent(BrowserAccessibility* parent,
+                                        int index_in_parent) {
+  parent_ = parent;
+  index_in_parent_ = index_in_parent;
+}
+
+bool BrowserAccessibility::IsDescendantOf(
+    BrowserAccessibility* ancestor) {
+  if (this == ancestor) {
+    return true;
+  } else if (parent_) {
+    return parent_->IsDescendantOf(ancestor);
+  }
+
+  return false;
+}
+
+BrowserAccessibility* BrowserAccessibility::GetChild(uint32 child_index) {
+  DCHECK(child_index < children_.size());
+  return children_[child_index];
+}
+
+BrowserAccessibility* BrowserAccessibility::GetPreviousSibling() {
+  if (parent_ && index_in_parent_ > 0)
+    return parent_->children_[index_in_parent_ - 1];
+
+  return NULL;
+}
+
+BrowserAccessibility* BrowserAccessibility::GetNextSibling() {
+  if (parent_ &&
+      index_in_parent_ >= 0 &&
+      index_in_parent_ < static_cast<int>(parent_->children_.size() - 1)) {
+    return parent_->children_[index_in_parent_ + 1];
+  }
+
+  return NULL;
+}
+
+gfx::Rect BrowserAccessibility::GetBoundsRect() {
+  gfx::Rect bounds = location_;
+
+  // Adjust the bounds by the top left corner of the containing view's bounds
+  // in screen coordinates.
+  gfx::Point top_left = manager_->GetViewBounds().origin();
+  bounds.Offset(top_left);
+
+  // Adjust top left position by the root document's scroll offset.
+  BrowserAccessibility* root = manager_->GetRoot();
+  int scroll_x = 0;
+  int scroll_y = 0;
+  root->GetAttributeAsInt(
+    WebAccessibility::ATTR_DOC_SCROLLX, &scroll_x);
+  root->GetAttributeAsInt(
+    WebAccessibility::ATTR_DOC_SCROLLY, &scroll_y);
+  bounds.Offset(-scroll_x, -scroll_y);
+
+  return bounds;
+}
+
+BrowserAccessibility* BrowserAccessibility::BrowserAccessibilityForPoint(
+    const gfx::Point& point) {
+  // Walk the children recursively looking for the BrowserAccessibility that
+  // most tightly encloses the specified point.
+  for (int i = children_.size() - 1; i >= 0; --i) {
+    BrowserAccessibility* child = children_[i];
+    if (child->GetBoundsRect().Contains(point))
+      return child->BrowserAccessibilityForPoint(point);
+  }
+  return this;
+}
+
+void BrowserAccessibility::InternalAddReference() {
+  ref_count_++;
+}
+
+void BrowserAccessibility::InternalReleaseReference(bool recursive) {
+  DCHECK_GT(ref_count_, 0);
+
+  if (recursive || ref_count_ == 1) {
+    for (std::vector<BrowserAccessibility*>::iterator iter = children_.begin();
+         iter != children_.end();
+         ++iter) {
+      (*iter)->InternalReleaseReference(true);
+    }
+  }
+
+  ref_count_--;
+  if (ref_count_ == 0) {
+    instance_active_ = false;
+    children_.clear();
+    manager_->Remove(child_id_, renderer_id_);
+    NativeReleaseReference();
+  }
+}
+
+void BrowserAccessibility::NativeReleaseReference() {
+  delete this;
+}
+
+bool BrowserAccessibility::HasAttribute(
+    WebAccessibility::Attribute attribute) {
+  return (attributes_.find(attribute) != attributes_.end());
+}
+
+bool BrowserAccessibility::GetAttribute(
+    WebAccessibility::Attribute attribute, string16* value) {
+  std::map<int32, string16>::iterator iter = attributes_.find(attribute);
+  if (iter != attributes_.end()) {
+    *value = iter->second;
+    return true;
+  }
+
+  return false;
+}
+
+bool BrowserAccessibility::GetAttributeAsInt(
+    WebAccessibility::Attribute attribute, int* value_int) {
+  string16 value_str;
+
+  if (!GetAttribute(attribute, &value_str))
+    return false;
+
+  if (!base::StringToInt(value_str, value_int))
+    return false;
+
+  return true;
+}
diff --git a/content/browser/accessibility/browser_accessibility.h b/content/browser/accessibility/browser_accessibility.h
new file mode 100644
index 0000000..dbd3e13
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility.h
@@ -0,0 +1,227 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_H_
+#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_H_
+#pragma once
+
+#include <map>
+#include <utility>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "build/build_config.h"
+#include "webkit/glue/webaccessibility.h"
+
+class BrowserAccessibilityManager;
+#if defined(OS_MACOSX) && __OBJC__
+@class BrowserAccessibilityCocoa;
+#elif defined(OS_WIN)
+class BrowserAccessibilityWin;
+#endif
+
+using webkit_glue::WebAccessibility;
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// BrowserAccessibility
+//
+// Class implementing the cross platform interface for the Browser-Renderer
+// communication of accessibility information, providing accessibility
+// to be used by screen readers and other assistive technology (AT).
+//
+// An implementation for each platform handles platform specific accessibility
+// APIs.
+//
+////////////////////////////////////////////////////////////////////////////////
+class BrowserAccessibility {
+ public:
+  // Creates a platform specific BrowserAccessibility. Ownership passes to the
+  // caller.
+  static BrowserAccessibility* Create();
+
+  virtual ~BrowserAccessibility();
+
+  // Detach all descendants of this subtree and push all of the node pointers,
+  // including this node, onto the end of |nodes|.
+  virtual void DetachTree(std::vector<BrowserAccessibility*>* nodes);
+
+  // Perform platform specific initialization. This can be called multiple times
+  // during the lifetime of this instance after the members of this base object
+  // have been reset with new values from the renderer process.
+  virtual void Initialize();
+
+  // Initialize this object, reading attributes from |src|. Does not
+  // recurse into children of |src| and build the whole subtree.
+  void Initialize(BrowserAccessibilityManager* manager,
+                  BrowserAccessibility* parent,
+                  int32 child_id,
+                  int32 index_in_parent,
+                  const WebAccessibility& src);
+
+  // Add a child of this object.
+  void AddChild(BrowserAccessibility* child);
+
+  // Update the parent and index in parent if this node has been moved.
+  void UpdateParent(BrowserAccessibility* parent, int index_in_parent);
+
+  // Return true if this object is equal to or a descendant of |ancestor|.
+  bool IsDescendantOf(BrowserAccessibility* ancestor);
+
+  // Returns the parent of this object, or NULL if it's the root.
+  BrowserAccessibility* parent() { return parent_; }
+
+  // Returns the number of children of this object.
+  uint32 child_count() const { return children_.size(); }
+
+  // Return a pointer to the child with the given index.
+  BrowserAccessibility* GetChild(uint32 child_index);
+
+  // Return the previous sibling of this object, or NULL if it's the first
+  // child of its parent.
+  BrowserAccessibility* GetPreviousSibling();
+
+  // Return the next sibling of this object, or NULL if it's the last child
+  // of its parent.
+  BrowserAccessibility* GetNextSibling();
+
+  // Returns the bounds of this object in screen coordinates.
+  gfx::Rect GetBoundsRect();
+
+  // Returns the deepest descendant that contains the specified point.
+  BrowserAccessibility* BrowserAccessibilityForPoint(const gfx::Point& point);
+
+  //
+  // Reference counting
+  //
+  // Each object has an internal reference count and many platform
+  // implementations may also use native reference counting.
+  //
+  // The internal reference counting is used because sometimes
+  // multiple references to the same object exist temporarily during
+  // an update. When the internal reference count reaches zero,
+  // NativeReleaseReference is called.
+  //
+  // Native reference counting is used on some platforms because the
+  // operating system may hold onto a reference to a BrowserAccessibility
+  // object even after we're through with it. On these platforms, when
+  // the internal reference count reaches zero, instance_active is set
+  // to zero, and all queries on this object should return failure.
+  // The object isn't actually deleted until the operating system releases
+  // all of its references.
+  //
+
+  // Increment this node's internal reference count.
+  virtual void InternalAddReference();
+
+  // Decrement this node's internal reference count. If the reference count
+  // reaches zero, call NativeReleaseReference().
+  virtual void InternalReleaseReference(bool recursive);
+
+  // Subclasses should override this to support platform reference counting.
+  virtual void NativeAddReference() { }
+
+  // Subclasses should override this to support platform reference counting.
+  virtual void NativeReleaseReference();
+
+  //
+  // Accessors
+  //
+
+  const std::map<int32, string16>& attributes() const { return attributes_; }
+  int32 child_id() const { return child_id_; }
+  const std::vector<BrowserAccessibility*>& children() const {
+    return children_;
+  }
+  const std::vector<std::pair<string16, string16> >& html_attributes() const {
+    return html_attributes_;
+  }
+  int32 index_in_parent() const { return index_in_parent_; }
+  const std::vector<int32>& indirect_child_ids() const {
+    return indirect_child_ids_;
+  }
+  const std::vector<int32>& line_breaks() const {
+    return line_breaks_;
+  }
+  gfx::Rect location() const { return location_; }
+  BrowserAccessibilityManager* manager() const { return manager_; }
+  const string16& name() const { return name_; }
+  int32 renderer_id() const { return renderer_id_; }
+  int32 role() const { return role_; }
+  const string16& role_name() const { return role_name_; }
+  int32 state() const { return state_; }
+  const string16& value() const { return value_; }
+  bool instance_active() const { return instance_active_; }
+  int32 ref_count() const { return ref_count_; }
+
+#if defined(OS_MACOSX) && __OBJC__
+  BrowserAccessibilityCocoa* toBrowserAccessibilityCocoa();
+#elif defined(OS_WIN)
+  BrowserAccessibilityWin* toBrowserAccessibilityWin();
+#endif
+
+  // BrowserAccessibilityCocoa needs access to these methods.
+  // Return true if this attribute is in the attributes map.
+  bool HasAttribute(WebAccessibility::Attribute attribute);
+
+  // Retrieve the string value of an attribute from the attribute map and
+  // returns true if found.
+  bool GetAttribute(WebAccessibility::Attribute attribute, string16* value);
+
+  // Retrieve the value of an attribute from the attribute map and
+  // if found and nonempty, try to convert it to an integer.
+  // Returns true only if both the attribute was found and it was successfully
+  // converted to an integer.
+  bool GetAttributeAsInt(
+      WebAccessibility::Attribute attribute, int* value_int);
+
+ protected:
+  BrowserAccessibility();
+
+  // The manager of this tree of accessibility objects; needed for
+  // global operations like focus tracking.
+  BrowserAccessibilityManager* manager_;
+
+  // The parent of this object, may be NULL if we're the root object.
+  BrowserAccessibility* parent_;
+
+  // The ID of this object; globally unique within the browser process.
+  int32 child_id_;
+
+  // The index of this within its parent object.
+  int32 index_in_parent_;
+
+  // The ID of this object in the renderer process.
+  int32 renderer_id_;
+
+  // The children of this object.
+  std::vector<BrowserAccessibility*> children_;
+
+  // The number of internal references to this object.
+  int32 ref_count_;
+
+  // Accessibility metadata from the renderer
+  string16 name_;
+  string16 value_;
+  std::map<int32, string16> attributes_;
+  std::vector<std::pair<string16, string16> > html_attributes_;
+  int32 role_;
+  int32 state_;
+  string16 role_name_;
+  gfx::Rect location_;
+  std::vector<int32> indirect_child_ids_;
+  std::vector<int32> line_breaks_;
+
+  // BrowserAccessibility objects are reference-counted on some platforms.
+  // When we're done with this object and it's removed from our accessibility
+  // tree, a client may still be holding onto a pointer to this object, so
+  // we mark it as inactive so that calls to any of this object's methods
+  // immediately return failure.
+  bool instance_active_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(BrowserAccessibility);
+};
+
+#endif  // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_H_
diff --git a/content/browser/accessibility/browser_accessibility_cocoa.h b/content/browser/accessibility/browser_accessibility_cocoa.h
new file mode 100644
index 0000000..ab4044f
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_cocoa.h
@@ -0,0 +1,76 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_COCOA_H_
+#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_COCOA_H_
+#pragma once
+
+#import <Cocoa/Cocoa.h>
+
+#import "base/memory/scoped_nsobject.h"
+#import "content/browser/accessibility/browser_accessibility_delegate_mac.h"
+#include "content/browser/accessibility/browser_accessibility.h"
+
+// BrowserAccessibilityCocoa is a cocoa wrapper around the BrowserAccessibility
+// object. The renderer converts webkit's accessibility tree into a
+// WebAccessibility tree and passes it to the browser process over IPC.
+// This class converts it into a format Cocoa can query.
+// Inheriting from NSView rather than NSObject as clients cannot add
+// observers to pure NSObject derived classes.
+@interface BrowserAccessibilityCocoa : NSView {
+ @private
+  BrowserAccessibility* browserAccessibility_;
+  scoped_nsobject<NSMutableArray> children_;
+  id<BrowserAccessibilityDelegateCocoa> delegate_;
+}
+
+// This creates a cocoa browser accessibility object around
+// the cross platform BrowserAccessibility object.  The delegate is
+// used to communicate with the host renderer.  None of these
+// parameters can be null.
+- (id)initWithObject:(BrowserAccessibility*)accessibility
+            delegate:(id<BrowserAccessibilityDelegateCocoa>)delegate;
+
+// Invalidate children for a non-ignored ancestor (including self).
+- (void)childrenChanged;
+
+// Children is an array of BrowserAccessibility objects, representing
+// the accessibility children of this object.
+@property(nonatomic, readonly) NSArray* children;
+@property(nonatomic, readonly) NSArray* columns;
+@property(nonatomic, readonly) NSString* description;
+@property(nonatomic, readonly) NSNumber* enabled;
+@property(nonatomic, readonly) NSNumber* focused;
+@property(nonatomic, readonly) NSString* help;
+// isIgnored returns whether or not the accessibility object
+// should be ignored by the accessibility hierarchy.
+@property(nonatomic, readonly, getter=isIgnored) BOOL ignored;
+// The origin of this object in the page's document.
+// This is relative to webkit's top-left origin, not Cocoa's
+// bottom-left origin.
+@property(nonatomic, readonly) NSPoint origin;
+@property(nonatomic, readonly) NSNumber* numberOfCharacters;
+@property(nonatomic, readonly) id parent;
+@property(nonatomic, readonly) NSValue* position;
+// A string indicating the role of this object as far as accessibility
+// is concerned.
+@property(nonatomic, readonly) NSString* role;
+@property(nonatomic, readonly) NSString* roleDescription;
+@property(nonatomic, readonly) NSArray* rows;
+// The size of this object.
+@property(nonatomic, readonly) NSValue* size;
+// A string indicating the subrole of this object as far as accessibility
+// is concerned.
+@property(nonatomic, readonly) NSString* subrole;
+// The tabs owned by a tablist.
+@property(nonatomic, readonly) NSArray* tabs;
+@property(nonatomic, readonly) NSString* title;
+@property(nonatomic, readonly) NSString* url;
+@property(nonatomic, readonly) NSString* value;
+@property(nonatomic, readonly) NSValue* visibleCharacterRange;
+@property(nonatomic, readonly) NSNumber* visited;
+@property(nonatomic, readonly) id window;
+@end
+
+#endif // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_COCOA_H_
diff --git a/content/browser/accessibility/browser_accessibility_cocoa.mm b/content/browser/accessibility/browser_accessibility_cocoa.mm
new file mode 100644
index 0000000..1920493
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_cocoa.mm
@@ -0,0 +1,822 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <execinfo.h>
+
+#import "content/browser/accessibility/browser_accessibility_cocoa.h"
+
+#include <map>
+
+#include "base/string16.h"
+#include "base/sys_string_conversions.h"
+#include "base/utf_string_conversions.h"
+#include "content/browser/accessibility/browser_accessibility_manager.h"
+#include "grit/webkit_strings.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebRect.h"
+#include "ui/base/l10n/l10n_util_mac.h"
+
+namespace {
+
+// Returns an autoreleased copy of the WebAccessibility's attribute.
+NSString* NSStringForWebAccessibilityAttribute(
+    const std::map<int32, string16>& attributes,
+    WebAccessibility::Attribute attribute) {
+  std::map<int32, string16>::const_iterator iter =
+      attributes.find(attribute);
+  NSString* returnValue = @"";
+  if (iter != attributes.end()) {
+    returnValue = base::SysUTF16ToNSString(iter->second);
+  }
+  return returnValue;
+}
+
+struct MapEntry {
+  WebAccessibility::Role webKitValue;
+  NSString* nativeValue;
+};
+
+struct AttributeToMethodNameEntry {
+  NSString* attribute;
+  NSString* methodName;
+};
+
+static const MapEntry roles[] = {
+  { WebAccessibility::ROLE_NONE, NSAccessibilityUnknownRole },
+  { WebAccessibility::ROLE_ALERT, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_ALERT_DIALOG, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_ANNOTATION, NSAccessibilityUnknownRole },
+  { WebAccessibility::ROLE_APPLICATION, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_ARTICLE, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_BROWSER, NSAccessibilityBrowserRole },
+  { WebAccessibility::ROLE_BUSY_INDICATOR, NSAccessibilityBusyIndicatorRole },
+  { WebAccessibility::ROLE_BUTTON, NSAccessibilityButtonRole },
+  { WebAccessibility::ROLE_CELL, @"AXCell" },
+  { WebAccessibility::ROLE_CHECKBOX, NSAccessibilityCheckBoxRole },
+  { WebAccessibility::ROLE_COLOR_WELL, NSAccessibilityColorWellRole },
+  { WebAccessibility::ROLE_COLUMN, NSAccessibilityColumnRole },
+  { WebAccessibility::ROLE_COLUMN_HEADER, @"AXCell" },
+  { WebAccessibility::ROLE_DEFINITION_LIST_DEFINITION,
+      NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_DEFINITION_LIST_TERM, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_DIALOG, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_DIRECTORY, NSAccessibilityListRole },
+  { WebAccessibility::ROLE_DISCLOSURE_TRIANGLE,
+      NSAccessibilityDisclosureTriangleRole },
+  { WebAccessibility::ROLE_DOCUMENT, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_DRAWER, NSAccessibilityDrawerRole },
+  { WebAccessibility::ROLE_EDITABLE_TEXT, NSAccessibilityTextFieldRole },
+  { WebAccessibility::ROLE_GRID, NSAccessibilityGridRole },
+  { WebAccessibility::ROLE_GROUP, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_GROW_AREA, NSAccessibilityGrowAreaRole },
+  { WebAccessibility::ROLE_HEADING, @"AXHeading" },
+  { WebAccessibility::ROLE_HELP_TAG, NSAccessibilityHelpTagRole },
+  { WebAccessibility::ROLE_IGNORED, NSAccessibilityUnknownRole },
+  { WebAccessibility::ROLE_IMAGE, NSAccessibilityImageRole },
+  { WebAccessibility::ROLE_IMAGE_MAP, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_IMAGE_MAP_LINK, NSAccessibilityLinkRole },
+  { WebAccessibility::ROLE_INCREMENTOR, NSAccessibilityIncrementorRole },
+  { WebAccessibility::ROLE_LANDMARK_APPLICATION, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_LANDMARK_BANNER, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_LANDMARK_COMPLEMENTARY, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_LANDMARK_CONTENTINFO, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_LANDMARK_MAIN, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_LANDMARK_NAVIGATION, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_LANDMARK_SEARCH, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_LINK, NSAccessibilityLinkRole },
+  { WebAccessibility::ROLE_LIST, NSAccessibilityListRole },
+  { WebAccessibility::ROLE_LIST_ITEM, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_LIST_MARKER, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_LISTBOX, NSAccessibilityListRole },
+  { WebAccessibility::ROLE_LISTBOX_OPTION, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_LOG, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_MARQUEE, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_MATH, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_MATTE, NSAccessibilityMatteRole },
+  { WebAccessibility::ROLE_MENU, NSAccessibilityMenuRole },
+  { WebAccessibility::ROLE_MENU_ITEM, NSAccessibilityMenuItemRole },
+  { WebAccessibility::ROLE_MENU_BUTTON, NSAccessibilityButtonRole },
+  { WebAccessibility::ROLE_MENU_LIST_OPTION, NSAccessibilityMenuItemRole },
+  { WebAccessibility::ROLE_MENU_LIST_POPUP, NSAccessibilityUnknownRole },
+  { WebAccessibility::ROLE_NOTE, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_OUTLINE, NSAccessibilityOutlineRole },
+  { WebAccessibility::ROLE_POPUP_BUTTON, NSAccessibilityPopUpButtonRole },
+  { WebAccessibility::ROLE_PROGRESS_INDICATOR,
+      NSAccessibilityProgressIndicatorRole },
+  { WebAccessibility::ROLE_RADIO_BUTTON, NSAccessibilityRadioButtonRole },
+  { WebAccessibility::ROLE_RADIO_GROUP, NSAccessibilityRadioGroupRole },
+  { WebAccessibility::ROLE_REGION, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_ROW, NSAccessibilityRowRole },
+  { WebAccessibility::ROLE_ROW_HEADER, @"AXCell" },
+  { WebAccessibility::ROLE_RULER, NSAccessibilityRulerRole },
+  { WebAccessibility::ROLE_RULER_MARKER, NSAccessibilityRulerMarkerRole },
+  { WebAccessibility::ROLE_SCROLLAREA, NSAccessibilityScrollAreaRole },
+  { WebAccessibility::ROLE_SCROLLBAR, NSAccessibilityScrollBarRole },
+  { WebAccessibility::ROLE_SHEET, NSAccessibilitySheetRole },
+  { WebAccessibility::ROLE_SLIDER, NSAccessibilitySliderRole },
+  { WebAccessibility::ROLE_SLIDER_THUMB, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_SPLITTER, NSAccessibilitySplitterRole },
+  { WebAccessibility::ROLE_SPLIT_GROUP, NSAccessibilitySplitGroupRole },
+  { WebAccessibility::ROLE_STATIC_TEXT, NSAccessibilityStaticTextRole },
+  { WebAccessibility::ROLE_STATUS, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_SYSTEM_WIDE, NSAccessibilityUnknownRole },
+  { WebAccessibility::ROLE_TAB, NSAccessibilityRadioButtonRole },
+  { WebAccessibility::ROLE_TAB_LIST, NSAccessibilityTabGroupRole },
+  { WebAccessibility::ROLE_TAB_PANEL, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_TABLE, NSAccessibilityTableRole },
+  { WebAccessibility::ROLE_TABLE_HEADER_CONTAINER, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_TAB_GROUP, NSAccessibilityTabGroupRole },
+  { WebAccessibility::ROLE_TEXTAREA, NSAccessibilityTextAreaRole },
+  { WebAccessibility::ROLE_TEXT_FIELD, NSAccessibilityTextFieldRole },
+  { WebAccessibility::ROLE_TIMER, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_TOOLBAR, NSAccessibilityToolbarRole },
+  { WebAccessibility::ROLE_TOOLTIP, NSAccessibilityGroupRole },
+  { WebAccessibility::ROLE_TREE, NSAccessibilityOutlineRole },
+  { WebAccessibility::ROLE_TREE_GRID, NSAccessibilityTableRole },
+  { WebAccessibility::ROLE_TREE_ITEM, NSAccessibilityRowRole },
+  { WebAccessibility::ROLE_VALUE_INDICATOR, NSAccessibilityValueIndicatorRole },
+  { WebAccessibility::ROLE_WEBCORE_LINK, NSAccessibilityLinkRole },
+  { WebAccessibility::ROLE_WEB_AREA, @"AXWebArea" },
+  { WebAccessibility::ROLE_WINDOW, NSAccessibilityUnknownRole },
+};
+
+static const MapEntry subroles[] = {
+  { WebAccessibility::ROLE_ALERT, @"AXApplicationAlert" },
+  { WebAccessibility::ROLE_ALERT_DIALOG, @"AXApplicationAlertDialog" },
+  { WebAccessibility::ROLE_ARTICLE, @"AXDocumentArticle" },
+  { WebAccessibility::ROLE_DEFINITION_LIST_DEFINITION, @"AXDefinition" },
+  { WebAccessibility::ROLE_DEFINITION_LIST_TERM, @"AXTerm" },
+  { WebAccessibility::ROLE_DIALOG, @"AXApplicationDialog" },
+  { WebAccessibility::ROLE_DOCUMENT, @"AXDocument" },
+  { WebAccessibility::ROLE_LANDMARK_APPLICATION, @"AXLandmarkApplication" },
+  { WebAccessibility::ROLE_LANDMARK_BANNER, @"AXLandmarkBanner" },
+  { WebAccessibility::ROLE_LANDMARK_COMPLEMENTARY, @"AXLandmarkComplementary" },
+  { WebAccessibility::ROLE_LANDMARK_CONTENTINFO, @"AXLandmarkContentInfo" },
+  { WebAccessibility::ROLE_LANDMARK_MAIN, @"AXLandmarkMain" },
+  { WebAccessibility::ROLE_LANDMARK_NAVIGATION, @"AXLandmarkNavigation" },
+  { WebAccessibility::ROLE_LANDMARK_SEARCH, @"AXLandmarkSearch" },
+  { WebAccessibility::ROLE_LOG, @"AXApplicationLog" },
+  { WebAccessibility::ROLE_MARQUEE, @"AXApplicationMarquee" },
+  { WebAccessibility::ROLE_MATH, @"AXDocumentMath" },
+  { WebAccessibility::ROLE_NOTE, @"AXDocumentNote" },
+  { WebAccessibility::ROLE_REGION, @"AXDocumentRegion" },
+  { WebAccessibility::ROLE_STATUS, @"AXApplicationStatus" },
+  { WebAccessibility::ROLE_TAB_PANEL, @"AXTabPanel" },
+  { WebAccessibility::ROLE_TIMER, @"AXApplicationTimer" },
+  { WebAccessibility::ROLE_TOOLTIP, @"AXUserInterfaceTooltip" },
+  { WebAccessibility::ROLE_TREE_ITEM, NSAccessibilityOutlineRowSubrole },
+};
+
+static const AttributeToMethodNameEntry attributeToMethodNameContainer[] = {
+  { NSAccessibilityChildrenAttribute, @"children" },
+  { NSAccessibilityColumnsAttribute, @"columns" },
+  { NSAccessibilityDescriptionAttribute, @"description" },
+  { NSAccessibilityEnabledAttribute, @"enabled" },
+  { NSAccessibilityFocusedAttribute, @"focused" },
+  { NSAccessibilityHelpAttribute, @"help" },
+  { NSAccessibilityNumberOfCharactersAttribute, @"numberOfCharacters" },
+  { NSAccessibilityParentAttribute, @"parent" },
+  { NSAccessibilityPositionAttribute, @"position" },
+  { NSAccessibilityRoleAttribute, @"role" },
+  { NSAccessibilityRoleDescriptionAttribute, @"roleDescription" },
+  { NSAccessibilityRowsAttribute, @"rows" },
+  { NSAccessibilitySizeAttribute, @"size" },
+  { NSAccessibilitySubroleAttribute, @"subrole" },
+  { NSAccessibilityTabsAttribute, @"tabs" },
+  { NSAccessibilityTitleAttribute, @"title" },
+  { NSAccessibilityTopLevelUIElementAttribute, @"window" },
+  { NSAccessibilityURLAttribute, @"url" },
+  { NSAccessibilityValueAttribute, @"value" },
+  { NSAccessibilityVisibleCharacterRangeAttribute, @"visibleCharacterRange" },
+  { NSAccessibilityWindowAttribute, @"window" },
+  { @"AXVisited", @"visited" },
+};
+
+// GetState checks the bitmask used in webaccessibility.h to check
+// if the given state was set on the accessibility object.
+bool GetState(BrowserAccessibility* accessibility, int state) {
+  return ((accessibility->state() >> state) & 1);
+}
+
+// A mapping of webkit roles to native roles.
+std::map<WebAccessibility::Role, NSString*> webAccessibilityToNativeRole;
+// A mapping of webkit roles to native subroles.
+std::map<WebAccessibility::Role, NSString*> webAccessibilityToNativeSubrole;
+// A mapping from an accessibility attribute to its method name.
+NSDictionary* attributeToMethodNameMap = nil;
+
+} // namespace
+
+@implementation BrowserAccessibilityCocoa
+
++ (void)initialize {
+  const size_t numRoles = sizeof(roles) / sizeof(roles[0]);
+  for (size_t i = 0; i < numRoles; ++i) {
+    webAccessibilityToNativeRole[roles[i].webKitValue] = roles[i].nativeValue;
+  }
+
+  const size_t numSubroles = sizeof(subroles) / sizeof(subroles[0]);
+  for (size_t i = 0; i < numSubroles; ++i) {
+    webAccessibilityToNativeSubrole[subroles[i].webKitValue] =
+        subroles[i].nativeValue;
+  }
+
+  NSMutableDictionary* dict = [[NSMutableDictionary alloc] init];
+  const size_t numAttributes = sizeof(attributeToMethodNameContainer) /
+                               sizeof(attributeToMethodNameContainer[0]);
+  for (size_t i = 0; i < numAttributes; ++i) {
+    [dict setObject:attributeToMethodNameContainer[i].methodName
+             forKey:attributeToMethodNameContainer[i].attribute];
+  }
+  attributeToMethodNameMap = dict;
+  dict = nil;
+}
+
+- (id)initWithObject:(BrowserAccessibility*)accessibility
+            delegate:(id<BrowserAccessibilityDelegateCocoa>)delegate {
+  if ((self = [super init])) {
+    browserAccessibility_ = accessibility;
+    delegate_ = delegate;
+  }
+  return self;
+}
+
+// Deletes our associated BrowserAccessibilityMac.
+- (void)dealloc {
+  if (browserAccessibility_) {
+    delete browserAccessibility_;
+    browserAccessibility_ = NULL;
+  }
+
+  [super dealloc];
+}
+
+// Returns an array of BrowserAccessibilityCocoa objects, representing the
+// accessibility children of this object.
+- (NSArray*)children {
+  if (!children_.get()) {
+    children_.reset([[NSMutableArray alloc]
+        initWithCapacity:browserAccessibility_->child_count()] );
+    for (uint32 index = 0;
+         index < browserAccessibility_->child_count();
+         ++index) {
+      BrowserAccessibilityCocoa* child =
+          browserAccessibility_->GetChild(index)->toBrowserAccessibilityCocoa();
+      if ([child isIgnored])
+        [children_ addObjectsFromArray:[child children]];
+      else
+        [children_ addObject:child];
+    }
+
+    // Also, add indirect children (if any).
+    for (uint32 i = 0;
+         i < browserAccessibility_->indirect_child_ids().size();
+         ++i) {
+      int32 child_id = browserAccessibility_->indirect_child_ids()[i];
+      BrowserAccessibilityCocoa* child =
+          browserAccessibility_->manager()->GetFromRendererID(child_id)->
+              toBrowserAccessibilityCocoa();
+      [children_ addObject:child];
+    }
+  }
+  return children_;
+}
+
+- (void)childrenChanged {
+  if (![self isIgnored]) {
+    children_.reset();
+  } else {
+    [browserAccessibility_->parent()->toBrowserAccessibilityCocoa()
+       childrenChanged];
+  }
+}
+
+- (NSArray*)columns {
+  NSMutableArray* ret = [[[NSMutableArray alloc] init] autorelease];
+  for (BrowserAccessibilityCocoa* child in [self children]) {
+    if ([[child role] isEqualToString:NSAccessibilityColumnRole])
+      [ret addObject:child];
+  }
+  return ret;
+}
+
+- (NSString*)description {
+  return NSStringForWebAccessibilityAttribute(
+      browserAccessibility_->attributes(),
+      WebAccessibility::ATTR_DESCRIPTION);
+}
+
+- (NSNumber*)enabled {
+  return [NSNumber numberWithBool:
+      !GetState(browserAccessibility_, WebAccessibility::STATE_UNAVAILABLE)];
+}
+
+- (NSNumber*)focused {
+  NSNumber* ret = [NSNumber numberWithBool:
+      GetState(browserAccessibility_, WebAccessibility::STATE_FOCUSED)];
+  return ret;
+}
+
+- (NSString*)help {
+  return NSStringForWebAccessibilityAttribute(
+      browserAccessibility_->attributes(),
+      WebAccessibility::ATTR_HELP);
+}
+
+// Returns whether or not this node should be ignored in the
+// accessibility tree.
+- (BOOL)isIgnored {
+  return [[self role] isEqualToString:NSAccessibilityUnknownRole];
+}
+
+- (NSNumber*)loaded {
+  return [NSNumber numberWithBool:YES];
+}
+
+// The origin of this accessibility object in the page's document.
+// This is relative to webkit's top-left origin, not Cocoa's
+// bottom-left origin.
+- (NSPoint)origin {
+  return NSMakePoint(browserAccessibility_->location().x(),
+                     browserAccessibility_->location().y());
+}
+
+- (NSNumber*)numberOfCharacters {
+  return [NSNumber numberWithInt:browserAccessibility_->value().length()];
+}
+
+- (id)parent {
+  // A nil parent means we're the root.
+  if (browserAccessibility_->parent()) {
+    return NSAccessibilityUnignoredAncestor(
+        browserAccessibility_->parent()->toBrowserAccessibilityCocoa());
+  } else {
+    // Hook back up to RenderWidgetHostViewCocoa.
+    return browserAccessibility_->manager()->GetParentView();
+  }
+}
+
+- (NSValue*)position {
+  return [NSValue valueWithPoint:[delegate_ accessibilityPointInScreen:self]];
+}
+
+// Returns a string indicating the role of this object.
+- (NSString*)role {
+  WebAccessibility::Role browserAccessibilityRole =
+      static_cast<WebAccessibility::Role>( browserAccessibility_->role());
+
+  // Roles that we only determine at runtime.
+  if (browserAccessibilityRole == WebAccessibility::ROLE_TEXT_FIELD &&
+      GetState(browserAccessibility_, WebAccessibility::STATE_PROTECTED)) {
+    return @"AXSecureTextField";
+  }
+
+  std::map<WebAccessibility::Role, NSString*>::iterator it =
+      webAccessibilityToNativeRole.find(browserAccessibilityRole);
+
+  if (it != webAccessibilityToNativeRole.end())
+    return it->second;
+  else
+    return NSAccessibilityUnknownRole;
+}
+
+// Returns a string indicating the role description of this object.
+- (NSString*)roleDescription {
+  NSString* role = [self role];
+  // The following descriptions are specific to webkit.
+  if ([role isEqualToString:@"AXWebArea"])
+    return l10n_util::GetNSString(IDS_AX_ROLE_WEB_AREA);
+
+  if ([role isEqualToString:@"NSAccessibilityLinkRole"])
+    return l10n_util::GetNSString(IDS_AX_ROLE_LINK);
+
+  if ([role isEqualToString:@"AXHeading"])
+    return l10n_util::GetNSString(IDS_AX_ROLE_HEADING);
+
+  if ([role isEqualToString:NSAccessibilityGroupRole] ||
+      [role isEqualToString:NSAccessibilityRadioButtonRole]) {
+    const std::vector<std::pair<string16, string16> >& htmlAttributes =
+        browserAccessibility_->html_attributes();
+    WebAccessibility::Role browserAccessibilityRole =
+        static_cast<WebAccessibility::Role>(browserAccessibility_->role());
+
+    if ((browserAccessibilityRole != WebAccessibility::ROLE_GROUP &&
+         browserAccessibilityRole != WebAccessibility::ROLE_LIST_ITEM) ||
+         browserAccessibilityRole == WebAccessibility::ROLE_TAB) {
+      for (size_t i = 0; i < htmlAttributes.size(); ++i) {
+        const std::pair<string16, string16>& htmlAttribute = htmlAttributes[i];
+        if (htmlAttribute.first == ASCIIToUTF16("role")) {
+          // TODO(dtseng): This is not localized; see crbug/84814.
+          return base::SysUTF16ToNSString(htmlAttribute.second);
+        }
+      }
+    }
+  }
+
+  return NSAccessibilityRoleDescription(role, nil);
+}
+
+- (NSArray*)rows {
+  NSMutableArray* ret = [[[NSMutableArray alloc] init] autorelease];
+  for (BrowserAccessibilityCocoa* child in [self children]) {
+    if ([[child role] isEqualToString:NSAccessibilityRowRole])
+      [ret addObject:child];
+  }
+
+  return ret;
+}
+
+// Returns the size of this object.
+- (NSValue*)size {
+  return  [NSValue valueWithSize:NSMakeSize(
+      browserAccessibility_->location().width(),
+      browserAccessibility_->location().height())];
+}
+
+// Returns a subrole based upon the role.
+- (NSString*) subrole {
+  // TODO: support password field -> NSAccessibilitySecureTextFieldSubrole
+  // TODO: support attachments
+  // TODO: support lists -> NSAccessibilityContentListSubrole ||
+  //                        NSAccessibilityDefinitionListSubrole
+
+  WebAccessibility::Role browserAccessibilityRole =
+      static_cast<WebAccessibility::Role>( browserAccessibility_->role());
+
+  std::map<WebAccessibility::Role, NSString*>::iterator it =
+      webAccessibilityToNativeSubrole.find(browserAccessibilityRole);
+
+  if (it != webAccessibilityToNativeSubrole.end())
+    return it->second;
+  else
+    return nil;
+}
+
+// Returns all tabs in this subtree.
+- (NSArray*)tabs {
+  NSMutableArray* tabSubtree = [[[NSMutableArray alloc] init] autorelease];
+
+  if (browserAccessibility_->role() == WebAccessibility::ROLE_TAB)
+    [tabSubtree addObject:self];
+
+  for (uint i=0; i < [[self children] count]; ++i) {
+    NSArray* tabChildren = [[[self children] objectAtIndex:i] tabs];
+    if ([tabChildren count] > 0)
+      [tabSubtree addObjectsFromArray:tabChildren];
+  }
+
+  return tabSubtree;
+}
+
+- (NSString*)title {
+  return base::SysUTF16ToNSString(browserAccessibility_->name());
+}
+
+- (NSString*)url {
+  WebAccessibility::Attribute urlAttribute =
+      [[self role] isEqualToString:@"AXWebArea"] ?
+          WebAccessibility::ATTR_DOC_URL :
+          WebAccessibility::ATTR_URL;
+  return NSStringForWebAccessibilityAttribute(
+      browserAccessibility_->attributes(),
+      urlAttribute);
+}
+
+- (id)value {
+  // WebCore uses an attachmentView to get the below behavior.
+  // We do not have any native views backing this object, so need
+  // to approximate Cocoa ax behavior best as we can.
+  NSString* role = [self role];
+  if ([role isEqualToString:@"AXHeading"]) {
+    NSString* headingLevel =
+        NSStringForWebAccessibilityAttribute(
+            browserAccessibility_->attributes(),
+            WebAccessibility::ATTR_HTML_TAG);
+    if ([headingLevel length] >= 2) {
+      return [NSNumber numberWithInt:
+          [[headingLevel substringFromIndex:1] intValue]];
+    }
+  } else if ([role isEqualToString:NSAccessibilityButtonRole]) {
+    // AXValue does not make sense for pure buttons.
+    return @"";
+  } else if ([role isEqualToString:NSAccessibilityCheckBoxRole] ||
+             [role isEqualToString:NSAccessibilityRadioButtonRole]) {
+    return [NSNumber numberWithInt:GetState(
+        browserAccessibility_, WebAccessibility::STATE_CHECKED) ? 1 : 0];
+  }
+  return base::SysUTF16ToNSString(browserAccessibility_->value());
+}
+
+- (NSValue*)visibleCharacterRange {
+  return [NSValue valueWithRange:
+      NSMakeRange(0, browserAccessibility_->value().length())];
+}
+
+- (NSNumber*)visited {
+  return [NSNumber numberWithBool:
+      GetState(browserAccessibility_, WebAccessibility::STATE_TRAVERSED)];
+}
+
+- (id)window {
+  return [delegate_ window];
+}
+
+// Returns the accessibility value for the given attribute.  If the value isn't
+// supported this will return nil.
+- (id)accessibilityAttributeValue:(NSString*)attribute {
+  SEL selector =
+      NSSelectorFromString([attributeToMethodNameMap objectForKey:attribute]);
+  if (selector)
+    return [self performSelector:selector];
+
+  // TODO(dtseng): refactor remaining attributes.
+  int selStart, selEnd;
+  if (browserAccessibility_->GetAttributeAsInt(
+          WebAccessibility::ATTR_TEXT_SEL_START, &selStart) &&
+      browserAccessibility_->
+          GetAttributeAsInt(WebAccessibility::ATTR_TEXT_SEL_END, &selEnd)) {
+    if (selStart > selEnd)
+      std::swap(selStart, selEnd);
+    int selLength = selEnd - selStart;
+    if ([attribute isEqualToString:
+        NSAccessibilityInsertionPointLineNumberAttribute]) {
+      const std::vector<int32>& line_breaks =
+          browserAccessibility_->line_breaks();
+      for (int i = 0; i < static_cast<int>(line_breaks.size()); ++i) {
+        if (line_breaks[i] > selStart)
+          return [NSNumber numberWithInt:i];
+      }
+      return [NSNumber numberWithInt:static_cast<int>(line_breaks.size())];
+    }
+    if ([attribute isEqualToString:NSAccessibilitySelectedTextAttribute]) {
+      return base::SysUTF16ToNSString(browserAccessibility_->value().substr(
+          selStart, selLength));
+    }
+    if ([attribute isEqualToString:NSAccessibilitySelectedTextRangeAttribute]) {
+      return [NSValue valueWithRange:NSMakeRange(selStart, selLength)];
+    }
+  }
+  return nil;
+}
+
+// Returns the accessibility value for the given attribute and parameter. If the
+// value isn't supported this will return nil.
+- (id)accessibilityAttributeValue:(NSString*)attribute
+                     forParameter:(id)parameter {
+  const std::vector<int32>& line_breaks = browserAccessibility_->line_breaks();
+  int len = static_cast<int>(browserAccessibility_->value().size());
+
+  if ([attribute isEqualToString:
+      NSAccessibilityStringForRangeParameterizedAttribute]) {
+    NSRange range = [(NSValue*)parameter rangeValue];
+    return base::SysUTF16ToNSString(
+        browserAccessibility_->value().substr(range.location, range.length));
+  }
+
+  if ([attribute isEqualToString:
+      NSAccessibilityLineForIndexParameterizedAttribute]) {
+    int index = [(NSNumber*)parameter intValue];
+    for (int i = 0; i < static_cast<int>(line_breaks.size()); ++i) {
+      if (line_breaks[i] > index)
+        return [NSNumber numberWithInt:i];
+    }
+    return [NSNumber numberWithInt:static_cast<int>(line_breaks.size())];
+  }
+
+  if ([attribute isEqualToString:
+      NSAccessibilityRangeForLineParameterizedAttribute]) {
+    int line_index = [(NSNumber*)parameter intValue];
+    int line_count = static_cast<int>(line_breaks.size()) + 1;
+    if (line_index < 0 || line_index >= line_count)
+      return nil;
+    int start = line_index > 0 ? line_breaks[line_index - 1] : 0;
+    int end = line_index < line_count - 1 ? line_breaks[line_index] : len;
+    return [NSValue valueWithRange:
+        NSMakeRange(start, end - start)];
+  }
+
+  // TODO(dtseng): support the following attributes.
+  if ([attribute isEqualTo:
+          NSAccessibilityRangeForPositionParameterizedAttribute] ||
+      [attribute isEqualTo:
+          NSAccessibilityRangeForIndexParameterizedAttribute] ||
+      [attribute isEqualTo:
+          NSAccessibilityBoundsForRangeParameterizedAttribute] ||
+      [attribute isEqualTo:NSAccessibilityRTFForRangeParameterizedAttribute] ||
+      [attribute isEqualTo:
+          NSAccessibilityStyleRangeForIndexParameterizedAttribute]) {
+    return nil;
+  }
+  return nil;
+}
+
+// Returns an array of parameterized attributes names that this object will
+// respond to.
+- (NSArray*)accessibilityParameterizedAttributeNames {
+  if ([[self role] isEqualToString:NSAccessibilityTextFieldRole] ||
+      [[self role] isEqualToString:NSAccessibilityTextAreaRole]) {
+    return [NSArray arrayWithObjects:
+        NSAccessibilityLineForIndexParameterizedAttribute,
+        NSAccessibilityRangeForLineParameterizedAttribute,
+        NSAccessibilityStringForRangeParameterizedAttribute,
+        NSAccessibilityRangeForPositionParameterizedAttribute,
+        NSAccessibilityRangeForIndexParameterizedAttribute,
+        NSAccessibilityBoundsForRangeParameterizedAttribute,
+        NSAccessibilityRTFForRangeParameterizedAttribute,
+        NSAccessibilityAttributedStringForRangeParameterizedAttribute,
+        NSAccessibilityStyleRangeForIndexParameterizedAttribute,
+        nil];
+  }
+  return nil;
+}
+
+// Returns an array of action names that this object will respond to.
+- (NSArray*)accessibilityActionNames {
+  NSMutableArray* ret =
+      [NSMutableArray arrayWithObject:NSAccessibilityShowMenuAction];
+  NSString* role = [self role];
+  // TODO(dtseng): this should only get set when there's a default action.
+  if (![role isEqualToString:NSAccessibilityStaticTextRole] &&
+      ![role isEqualToString:NSAccessibilityTextAreaRole] &&
+      ![role isEqualToString:NSAccessibilityTextFieldRole]) {
+    [ret addObject:NSAccessibilityPressAction];
+  }
+
+  return ret;
+}
+
+// Returns a sub-array of values for the given attribute value, starting at
+// index, with up to maxCount items.  If the given index is out of bounds,
+// or there are no values for the given attribute, it will return nil.
+// This method is used for querying subsets of values, without having to
+// return a large set of data, such as elements with a large number of
+// children.
+- (NSArray*)accessibilityArrayAttributeValues:(NSString*)attribute
+                                        index:(NSUInteger)index
+                                     maxCount:(NSUInteger)maxCount {
+  NSArray* fullArray = [self accessibilityAttributeValue:attribute];
+  if (!fullArray)
+    return nil;
+  NSUInteger arrayCount = [fullArray count];
+  if (index >= arrayCount)
+    return nil;
+  NSRange subRange;
+  if ((index + maxCount) > arrayCount) {
+    subRange = NSMakeRange(index, arrayCount - index);
+  } else {
+    subRange = NSMakeRange(index, maxCount);
+  }
+  return [fullArray subarrayWithRange:subRange];
+}
+
+// Returns the count of the specified accessibility array attribute.
+- (NSUInteger)accessibilityArrayAttributeCount:(NSString*)attribute {
+  NSArray* fullArray = [self accessibilityAttributeValue:attribute];
+  return [fullArray count];
+}
+
+// Returns the list of accessibility attributes that this object supports.
+- (NSArray*)accessibilityAttributeNames {
+  // General attributes.
+  NSMutableArray* ret = [NSMutableArray arrayWithObjects:
+      NSAccessibilityChildrenAttribute,
+      NSAccessibilityDescriptionAttribute,
+      NSAccessibilityEnabledAttribute,
+      NSAccessibilityFocusedAttribute,
+      NSAccessibilityHelpAttribute,
+      NSAccessibilityParentAttribute,
+      NSAccessibilityPositionAttribute,
+      NSAccessibilityRoleAttribute,
+      NSAccessibilityRoleDescriptionAttribute,
+      NSAccessibilitySizeAttribute,
+      NSAccessibilitySubroleAttribute,
+      NSAccessibilityTitleAttribute,
+      NSAccessibilityTopLevelUIElementAttribute,
+      NSAccessibilityValueAttribute,
+      NSAccessibilityWindowAttribute,
+      NSAccessibilityURLAttribute,
+      @"AXVisited",
+      nil];
+
+  // Specific role attributes.
+  NSString* role = [self role];
+  if ([role isEqualToString:NSAccessibilityTableRole]) {
+    [ret addObjectsFromArray:[NSArray arrayWithObjects:
+        NSAccessibilityColumnsAttribute,
+        NSAccessibilityRowsAttribute,
+        nil]];
+  } else if ([role isEqualToString:@"AXWebArea"]) {
+    [ret addObject:@"AXLoaded"];
+  } else if ([role isEqualToString:NSAccessibilityTextFieldRole] ||
+             [role isEqualToString:NSAccessibilityTextAreaRole]) {
+    [ret addObjectsFromArray:[NSArray arrayWithObjects:
+        NSAccessibilityInsertionPointLineNumberAttribute,
+        NSAccessibilityNumberOfCharactersAttribute,
+        NSAccessibilitySelectedTextAttribute,
+        NSAccessibilitySelectedTextRangeAttribute,
+        NSAccessibilityVisibleCharacterRangeAttribute,
+        nil]];
+  } else if ([role isEqualToString:NSAccessibilityTabGroupRole]) {
+    [ret addObject:NSAccessibilityTabsAttribute];
+  }
+
+  return ret;
+}
+
+// Returns the index of the child in this objects array of children.
+- (NSUInteger)accessibilityGetIndexOf:(id)child {
+  NSUInteger index = 0;
+  for (BrowserAccessibilityCocoa* childToCheck in [self children]) {
+    if ([child isEqual:childToCheck])
+      return index;
+    ++index;
+  }
+  return NSNotFound;
+}
+
+// Returns whether or not the specified attribute can be set by the
+// accessibility API via |accessibilitySetValue:forAttribute:|.
+- (BOOL)accessibilityIsAttributeSettable:(NSString*)attribute {
+  if ([attribute isEqualToString:NSAccessibilityFocusedAttribute])
+    return GetState(browserAccessibility_, WebAccessibility::STATE_FOCUSABLE);
+  if ([attribute isEqualToString:NSAccessibilityValueAttribute])
+    return !GetState(browserAccessibility_, WebAccessibility::STATE_READONLY);
+  return NO;
+}
+
+// Returns whether or not this object should be ignored in the accessibilty
+// tree.
+- (BOOL)accessibilityIsIgnored {
+  return [self isIgnored];
+}
+
+// Performs the given accessibilty action on the webkit accessibility object
+// that backs this object.
+- (void)accessibilityPerformAction:(NSString*)action {
+  // TODO(feldstein): Support more actions.
+  if ([action isEqualToString:NSAccessibilityPressAction])
+    [delegate_ doDefaultAction:browserAccessibility_->renderer_id()];
+  else if ([action isEqualToString:NSAccessibilityShowMenuAction])
+    [delegate_ performShowMenuAction:self];
+}
+
+// Returns the description of the given action.
+- (NSString*)accessibilityActionDescription:(NSString*)action {
+  return NSAccessibilityActionDescription(action);
+}
+
+// Sets an override value for a specific accessibility attribute.
+// This class does not support this.
+- (BOOL)accessibilitySetOverrideValue:(id)value
+                         forAttribute:(NSString*)attribute {
+  return NO;
+}
+
+// Sets the value for an accessibility attribute via the accessibility API.
+- (void)accessibilitySetValue:(id)value forAttribute:(NSString*)attribute {
+  if ([attribute isEqualToString:NSAccessibilityFocusedAttribute]) {
+    NSNumber* focusedNumber = value;
+    BOOL focused = [focusedNumber intValue];
+    [delegate_ setAccessibilityFocus:focused
+                     accessibilityId:browserAccessibility_->renderer_id()];
+  }
+}
+
+// Returns the deepest accessibility child that should not be ignored.
+// It is assumed that the hit test has been narrowed down to this object
+// or one of its children, so this will never return nil.
+- (id)accessibilityHitTest:(NSPoint)point {
+  BrowserAccessibilityCocoa* hit = self;
+  for (BrowserAccessibilityCocoa* child in [self children]) {
+    NSPoint origin = [child origin];
+    NSSize size = [[child size] sizeValue];
+    NSRect rect;
+    rect.origin = origin;
+    rect.size = size;
+    if (NSPointInRect(point, rect)) {
+      hit = child;
+      id childResult = [child accessibilityHitTest:point];
+      if (![childResult accessibilityIsIgnored]) {
+        hit = childResult;
+        break;
+      }
+    }
+  }
+  return NSAccessibilityUnignoredAncestor(hit);
+}
+
+- (BOOL)isEqual:(id)object {
+  if (![object isKindOfClass:[BrowserAccessibilityCocoa class]])
+    return NO;
+  return ([self hash] == [object hash]);
+}
+
+- (NSUInteger)hash {
+  // Potentially called during dealloc.
+  if (!browserAccessibility_)
+    return [super hash];
+  return browserAccessibility_->renderer_id();
+}
+
+@end
+
diff --git a/content/browser/accessibility/browser_accessibility_delegate_mac.h b/content/browser/accessibility/browser_accessibility_delegate_mac.h
new file mode 100644
index 0000000..680ab87
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_delegate_mac.h
@@ -0,0 +1,24 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_DELEGATE_MAC_H_
+#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_DELEGATE_MAC_H_
+#pragma once
+
+@class BrowserAccessibilityCocoa;
+@class NSWindow;
+
+// This protocol is used by the BrowserAccessibility objects to pass messages
+// to, or otherwise communicate with, their underlying WebAccessibility
+// objects over the IPC boundary.
+@protocol BrowserAccessibilityDelegateCocoa
+- (NSPoint)accessibilityPointInScreen:(BrowserAccessibilityCocoa*)accessibility;
+- (void)doDefaultAction:(int32)accessibilityObjectId;
+- (void)performShowMenuAction:(BrowserAccessibilityCocoa*)accessibility;
+- (void)setAccessibilityFocus:(BOOL)focus
+              accessibilityId:(int32)accessibilityObjectId;
+- (NSWindow*)window;
+@end
+
+#endif // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_DELEGATE_MAC_H_
diff --git a/content/browser/accessibility/browser_accessibility_mac.h b/content/browser/accessibility/browser_accessibility_mac.h
new file mode 100644
index 0000000..ee6cfca
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_mac.h
@@ -0,0 +1,46 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MAC_H_
+#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MAC_H_
+#pragma once
+
+#include <map>
+#include <utility>
+#include <vector>
+
+#include "base/memory/scoped_nsobject.h"
+#include "content/browser/accessibility/browser_accessibility.h"
+
+@class BrowserAccessibilityCocoa;
+
+class BrowserAccessibilityMac : public BrowserAccessibility {
+ public:
+  // Implementation of BrowserAccessibility.
+  virtual void Initialize();
+  virtual void NativeReleaseReference();
+
+  // Overrides from BrowserAccessibility.
+  virtual void DetachTree(std::vector<BrowserAccessibility*>* nodes);
+
+  // The BrowserAccessibilityCocoa associated with us.
+  BrowserAccessibilityCocoa* native_view() const {
+    return browser_accessibility_cocoa_;
+  }
+
+ private:
+  // This gives BrowserAccessibility::Create access to the class constructor.
+  friend class BrowserAccessibility;
+
+  BrowserAccessibilityMac();
+
+  // Allows access to the BrowserAccessibilityCocoa which wraps this.
+  // BrowserAccessibility.
+  // We own this object until our manager calls ReleaseReference;
+  // thereafter, the cocoa object owns us.
+  BrowserAccessibilityCocoa* browser_accessibility_cocoa_;
+  DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityMac);
+};
+
+#endif // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MAC_H_
diff --git a/content/browser/accessibility/browser_accessibility_mac.mm b/content/browser/accessibility/browser_accessibility_mac.mm
new file mode 100644
index 0000000..145294d
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_mac.mm
@@ -0,0 +1,59 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import <Cocoa/Cocoa.h>
+
+#import "content/browser/accessibility/browser_accessibility_mac.h"
+
+#import "content/browser/accessibility/browser_accessibility_cocoa.h"
+#import "content/browser/accessibility/browser_accessibility_delegate_mac.h"
+#include "content/browser/accessibility/browser_accessibility_manager.h"
+
+
+// Static.
+BrowserAccessibility* BrowserAccessibility::Create() {
+  return new BrowserAccessibilityMac();
+}
+
+BrowserAccessibilityMac::BrowserAccessibilityMac()
+    : browser_accessibility_cocoa_(NULL) {
+}
+
+void BrowserAccessibilityMac::Initialize() {
+  BrowserAccessibility::Initialize();
+
+  if (browser_accessibility_cocoa_)
+    return;
+
+  // We take ownership of the cocoa obj here.
+  browser_accessibility_cocoa_ = [[BrowserAccessibilityCocoa alloc]
+      initWithObject:this
+      delegate:
+          (id<BrowserAccessibilityDelegateCocoa>)manager_->GetParentView()];
+}
+
+void BrowserAccessibilityMac::NativeReleaseReference() {
+  if (browser_accessibility_cocoa_) {
+    BrowserAccessibilityCocoa* temp = browser_accessibility_cocoa_;
+    browser_accessibility_cocoa_ = nil;
+    // Relinquish ownership of the cocoa obj.
+    [temp release];
+    // At this point, other processes may have a reference to
+    // the cocoa object. When the retain count hits zero, it will
+    // destroy us in dealloc.
+    // For that reason, do *not* make any more calls here after
+    // as we might have been deleted.
+  }
+}
+
+void BrowserAccessibilityMac::DetachTree(
+    std::vector<BrowserAccessibility*>* nodes) {
+  [browser_accessibility_cocoa_ childrenChanged];
+  BrowserAccessibility::DetachTree(nodes);
+}
+
+BrowserAccessibilityCocoa* BrowserAccessibility::toBrowserAccessibilityCocoa() {
+  return static_cast<BrowserAccessibilityMac*>(this)->
+      native_view();
+}
diff --git a/content/browser/accessibility/browser_accessibility_manager.cc b/content/browser/accessibility/browser_accessibility_manager.cc
new file mode 100644
index 0000000..a99c782
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_manager.cc
@@ -0,0 +1,373 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/accessibility/browser_accessibility_manager.h"
+
+#include "base/logging.h"
+#include "content/browser/accessibility/browser_accessibility.h"
+#include "content/common/view_messages.h"
+
+using webkit_glue::WebAccessibility;
+
+BrowserAccessibility* BrowserAccessibilityFactory::Create() {
+  return BrowserAccessibility::Create();
+}
+
+// Start child IDs at -1 and decrement each time, because clients use
+// child IDs of 1, 2, 3, ... to access the children of an object by
+// index, so we use negative IDs to clearly distinguish between indices
+// and unique IDs.
+// static
+int32 BrowserAccessibilityManager::next_child_id_ = -1;
+
+#if defined(OS_POSIX) && !defined(OS_MACOSX)
+// There's no OS-specific implementation of BrowserAccessibilityManager
+// on Unix, so just instantiate the base class.
+// static
+BrowserAccessibilityManager* BrowserAccessibilityManager::Create(
+    gfx::NativeView parent_view,
+    const WebAccessibility& src,
+    BrowserAccessibilityDelegate* delegate,
+    BrowserAccessibilityFactory* factory) {
+  return new BrowserAccessibilityManager(
+      parent_view, src, delegate, factory);
+}
+#endif
+
+BrowserAccessibilityManager::BrowserAccessibilityManager(
+    gfx::NativeView parent_view,
+    const WebAccessibility& src,
+    BrowserAccessibilityDelegate* delegate,
+    BrowserAccessibilityFactory* factory)
+    : parent_view_(parent_view),
+      delegate_(delegate),
+      factory_(factory),
+      focus_(NULL) {
+  root_ = CreateAccessibilityTree(NULL, src, 0);
+  if (!focus_)
+    SetFocus(root_, false);
+}
+
+// static
+int32 BrowserAccessibilityManager::GetNextChildID() {
+  // Get the next child ID, and wrap around when we get near the end
+  // of a 32-bit integer range. It's okay to wrap around; we just want
+  // to avoid it as long as possible because clients may cache the ID of
+  // an object for a while to determine if they've seen it before.
+  next_child_id_--;
+  if (next_child_id_ == -2000000000)
+    next_child_id_ = -1;
+
+  return next_child_id_;
+}
+
+BrowserAccessibilityManager::~BrowserAccessibilityManager() {
+  // Clients could still hold references to some nodes of the tree, so
+  // calling InternalReleaseReference will make sure that as many nodes
+  // as possible are released now, and remaining nodes are marked as
+  // inactive so that calls to any methods on them will fail gracefully.
+  focus_->InternalReleaseReference(false);
+  root_->InternalReleaseReference(true);
+}
+
+BrowserAccessibility* BrowserAccessibilityManager::GetRoot() {
+  return root_;
+}
+
+BrowserAccessibility* BrowserAccessibilityManager::GetFromChildID(
+    int32 child_id) {
+  base::hash_map<int32, BrowserAccessibility*>::iterator iter =
+      child_id_map_.find(child_id);
+  if (iter != child_id_map_.end()) {
+    return iter->second;
+  } else {
+    return NULL;
+  }
+}
+
+BrowserAccessibility* BrowserAccessibilityManager::GetFromRendererID(
+    int32 renderer_id) {
+  base::hash_map<int32, int32>::iterator iter =
+      renderer_id_to_child_id_map_.find(renderer_id);
+  if (iter == renderer_id_to_child_id_map_.end())
+    return NULL;
+
+  int32 child_id = iter->second;
+  return GetFromChildID(child_id);
+}
+
+void BrowserAccessibilityManager::Remove(int32 child_id, int32 renderer_id) {
+  child_id_map_.erase(child_id);
+  renderer_id_to_child_id_map_.erase(renderer_id);
+}
+
+void BrowserAccessibilityManager::OnAccessibilityNotifications(
+    const std::vector<ViewHostMsg_AccessibilityNotification_Params>& params) {
+  for (uint32 index = 0; index < params.size(); index++) {
+    const ViewHostMsg_AccessibilityNotification_Params& param = params[index];
+
+    switch (param.notification_type) {
+      case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_CHECK_STATE_CHANGED:
+        OnAccessibilityObjectStateChange(param.acc_obj);
+        break;
+      case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_CHILDREN_CHANGED:
+        OnAccessibilityObjectChildrenChange(param.acc_obj);
+        break;
+      case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_FOCUS_CHANGED:
+        OnAccessibilityObjectFocusChange(param.acc_obj);
+        break;
+      case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_LOAD_COMPLETE:
+        OnAccessibilityObjectLoadComplete(param.acc_obj);
+        break;
+      case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_VALUE_CHANGED:
+        OnAccessibilityObjectValueChange(param.acc_obj);
+        break;
+      case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_SELECTED_TEXT_CHANGED:
+        OnAccessibilityObjectTextChange(param.acc_obj);
+        break;
+      default:
+        DCHECK(0);
+        break;
+    }
+  }
+}
+
+void BrowserAccessibilityManager::OnAccessibilityObjectStateChange(
+    const WebAccessibility& acc_obj) {
+  BrowserAccessibility* new_browser_acc = UpdateNode(acc_obj, false);
+  if (!new_browser_acc)
+    return;
+
+  NotifyAccessibilityEvent(
+      ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_CHECK_STATE_CHANGED,
+      new_browser_acc);
+}
+
+void BrowserAccessibilityManager::OnAccessibilityObjectChildrenChange(
+    const WebAccessibility& acc_obj) {
+  BrowserAccessibility* new_browser_acc = UpdateNode(acc_obj, true);
+  if (!new_browser_acc)
+    return;
+
+  NotifyAccessibilityEvent(
+      ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_CHILDREN_CHANGED,
+      new_browser_acc);
+}
+
+void BrowserAccessibilityManager::OnAccessibilityObjectFocusChange(
+  const WebAccessibility& acc_obj) {
+  BrowserAccessibility* new_browser_acc = UpdateNode(acc_obj, false);
+  if (!new_browser_acc)
+    return;
+
+  SetFocus(new_browser_acc, false);
+  if (delegate_ && delegate_->HasFocus()) {
+    GotFocus();
+  } else if (!delegate_) {
+    // Mac currently does not have a BrowserAccessibilityDelegate.
+    NotifyAccessibilityEvent(
+        ViewHostMsg_AccessibilityNotification_Type::
+        NOTIFICATION_TYPE_FOCUS_CHANGED,
+        focus_);
+  }
+}
+
+void BrowserAccessibilityManager::OnAccessibilityObjectLoadComplete(
+  const WebAccessibility& acc_obj) {
+  SetFocus(NULL, false);
+  root_->InternalReleaseReference(true);
+
+  root_ = CreateAccessibilityTree(NULL, acc_obj, 0);
+  if (!focus_)
+    SetFocus(root_, false);
+
+  NotifyAccessibilityEvent(
+      ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_LOAD_COMPLETE,
+      root_);
+  if (delegate_ && delegate_->HasFocus())
+    GotFocus();
+}
+
+void BrowserAccessibilityManager::OnAccessibilityObjectValueChange(
+    const WebAccessibility& acc_obj) {
+  BrowserAccessibility* new_browser_acc = UpdateNode(acc_obj, false);
+  if (!new_browser_acc)
+    return;
+
+  NotifyAccessibilityEvent(
+      ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_VALUE_CHANGED,
+      new_browser_acc);
+}
+
+void BrowserAccessibilityManager::OnAccessibilityObjectTextChange(
+    const WebAccessibility& acc_obj) {
+  BrowserAccessibility* new_browser_acc = UpdateNode(acc_obj, false);
+  if (!new_browser_acc)
+    return;
+
+  NotifyAccessibilityEvent(
+      ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_SELECTED_TEXT_CHANGED,
+      new_browser_acc);
+}
+
+void BrowserAccessibilityManager::GotFocus() {
+  // TODO(ctguil): Remove when tree update logic handles focus changes.
+  if (!focus_)
+    return;
+
+  NotifyAccessibilityEvent(
+      ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_FOCUS_CHANGED,
+      focus_);
+}
+
+gfx::NativeView BrowserAccessibilityManager::GetParentView() {
+  return parent_view_;
+}
+
+BrowserAccessibility* BrowserAccessibilityManager::GetFocus(
+    BrowserAccessibility* root) {
+  if (focus_ && (!root || focus_->IsDescendantOf(root)))
+    return focus_;
+
+  return NULL;
+}
+
+void BrowserAccessibilityManager::SetFocus(
+    BrowserAccessibility* node, bool notify) {
+  if (focus_)
+    focus_->InternalReleaseReference(false);
+  focus_ = node;
+  if (focus_)
+    focus_->InternalAddReference();
+
+  if (notify && node && delegate_)
+    delegate_->SetAccessibilityFocus(node->renderer_id());
+}
+
+void BrowserAccessibilityManager::DoDefaultAction(
+    const BrowserAccessibility& node) {
+  if (delegate_)
+    delegate_->AccessibilityDoDefaultAction(node.renderer_id());
+}
+
+gfx::Rect BrowserAccessibilityManager::GetViewBounds() {
+  if (delegate_)
+    return delegate_->GetViewBounds();
+  return gfx::Rect();
+}
+
+BrowserAccessibility* BrowserAccessibilityManager::UpdateNode(
+    const WebAccessibility& src,
+    bool include_children) {
+  base::hash_map<int32, int32>::iterator iter =
+      renderer_id_to_child_id_map_.find(src.id);
+  if (iter == renderer_id_to_child_id_map_.end())
+    return NULL;
+
+  int32 child_id = iter->second;
+  BrowserAccessibility* current = GetFromChildID(child_id);
+  if (!current)
+    return NULL;
+
+  if (!include_children) {
+    DCHECK_EQ(0U, src.children.size());
+    current->Initialize(
+        this,
+        current->parent(),
+        current->child_id(),
+        current->index_in_parent(),
+        src);
+    return current;
+  }
+
+  BrowserAccessibility* current_parent = current->parent();
+  int current_index_in_parent = current->index_in_parent();
+
+  // Detach all of the nodes in the old tree and get a single flat vector
+  // of all node pointers.
+  std::vector<BrowserAccessibility*> old_tree_nodes;
+  current->DetachTree(&old_tree_nodes);
+
+  // Build a new tree, reusing old nodes if possible. Each node that's
+  // reused will have its reference count incremented by one.
+  current =
+      CreateAccessibilityTree(current_parent, src, current_index_in_parent);
+
+  // Decrement the reference count of all nodes in the old tree, which will
+  // delete any nodes no longer needed.
+  for (int i = 0; i < static_cast<int>(old_tree_nodes.size()); i++)
+    old_tree_nodes[i]->InternalReleaseReference(false);
+
+  DCHECK(focus_);
+  if (!focus_->instance_active())
+    SetFocus(root_, false);
+
+  return current;
+}
+
+BrowserAccessibility* BrowserAccessibilityManager::CreateAccessibilityTree(
+    BrowserAccessibility* parent,
+    const WebAccessibility& src,
+    int index_in_parent) {
+  BrowserAccessibility* instance = NULL;
+  int32 child_id = 0;
+  base::hash_map<int32, int32>::iterator iter =
+      renderer_id_to_child_id_map_.find(src.id);
+
+  // If a BrowserAccessibility instance for this ID already exists, add a
+  // new reference to it and retrieve its children vector.
+  if (iter != renderer_id_to_child_id_map_.end()) {
+    child_id = iter->second;
+    instance = GetFromChildID(child_id);
+  }
+
+  // If the node has changed roles, don't reuse a BrowserAccessibility
+  // object, that could confuse a screen reader.
+  if (instance && instance->role() != src.role)
+    instance = NULL;
+
+  // If we're reusing a node, it should already be detached from a parent
+  // and any children. If not, that means we have a serious bug somewhere,
+  // like the same child is reachable from two places in the same tree.
+  if (instance && (instance->parent() != NULL || instance->child_count() > 0)) {
+    NOTREACHED();
+    instance = NULL;
+  }
+
+  if (instance) {
+    // If we're reusing a node, update its parent and increment its
+    // reference count.
+    instance->UpdateParent(parent, index_in_parent);
+    instance->InternalAddReference();
+  } else {
+    // Otherwise, create a new instance.
+    instance = factory_->Create();
+    child_id = GetNextChildID();
+  }
+
+  instance->Initialize(this, parent, child_id, index_in_parent, src);
+  child_id_map_[child_id] = instance;
+  renderer_id_to_child_id_map_[src.id] = child_id;
+  if ((src.state >> WebAccessibility::STATE_FOCUSED) & 1)
+    SetFocus(instance, false);
+  for (int i = 0; i < static_cast<int>(src.children.size()); ++i) {
+    BrowserAccessibility* child = CreateAccessibilityTree(
+        instance, src.children[i], i);
+    instance->AddChild(child);
+  }
+
+  return instance;
+}
diff --git a/content/browser/accessibility/browser_accessibility_manager.h b/content/browser/accessibility/browser_accessibility_manager.h
new file mode 100644
index 0000000..bbb7d77
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_manager.h
@@ -0,0 +1,177 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_H_
+#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_H_
+#pragma once
+
+#include <vector>
+
+#include "base/hash_tables.h"
+#include "base/memory/scoped_ptr.h"
+#include "build/build_config.h"
+#include "ui/gfx/native_widget_types.h"
+#include "webkit/glue/webaccessibility.h"
+
+class BrowserAccessibility;
+#if defined(OS_WIN)
+class BrowserAccessibilityManagerWin;
+#endif
+
+struct ViewHostMsg_AccessibilityNotification_Params;
+
+using webkit_glue::WebAccessibility;
+
+// Class that can perform actions on behalf of the BrowserAccessibilityManager.
+class BrowserAccessibilityDelegate {
+ public:
+  virtual ~BrowserAccessibilityDelegate() {}
+  virtual void SetAccessibilityFocus(int acc_obj_id) = 0;
+  virtual void AccessibilityDoDefaultAction(int acc_obj_id) = 0;
+  virtual bool HasFocus() = 0;
+  virtual gfx::Rect GetViewBounds() const = 0;
+};
+
+class BrowserAccessibilityFactory {
+ public:
+  virtual ~BrowserAccessibilityFactory() {}
+
+  // Create an instance of BrowserAccessibility and return a new
+  // reference to it.
+  virtual BrowserAccessibility* Create();
+};
+
+// Manages a tree of BrowserAccessibility objects.
+class BrowserAccessibilityManager {
+ public:
+  // Creates the platform specific BrowserAccessibilityManager. Ownership passes
+  // to the caller.
+  static BrowserAccessibilityManager* Create(
+    gfx::NativeView parent_view,
+    const WebAccessibility& src,
+    BrowserAccessibilityDelegate* delegate,
+    BrowserAccessibilityFactory* factory = new BrowserAccessibilityFactory());
+
+  virtual ~BrowserAccessibilityManager();
+
+  // Type is a ViewHostMsg_AccessibilityNotification_Params::NotificationType.
+  // We pass it as int so that we don't include the render message declaration
+  // header here.
+  virtual void NotifyAccessibilityEvent(
+      int type,
+      BrowserAccessibility* node) { }
+
+  // Returns the next unique child id.
+  static int32 GetNextChildID();
+
+  // Return a pointer to the root of the tree, does not make a new reference.
+  BrowserAccessibility* GetRoot();
+
+  // Removes the BrowserAccessibility child_id and renderer_id from the manager.
+  void Remove(int32 child_id, int32 renderer_id);
+
+  // Return a pointer to the object corresponding to the given child_id,
+  // does not make a new reference.
+  BrowserAccessibility* GetFromChildID(int32 child_id);
+
+  // Return a pointer to the object corresponding to the given renderer_id,
+  // does not make a new reference.
+  BrowserAccessibility* GetFromRendererID(int32 renderer_id);
+
+  // Called to notify the accessibility manager that its associated native
+  // view got focused.
+  void GotFocus();
+
+  // Update the focused node to |node|, which may be null.
+  // If |notify| is true, send a message to the renderer to set focus
+  // to this node.
+  void SetFocus(BrowserAccessibility* node, bool notify);
+
+  // Tell the renderer to do the default action for this node.
+  void DoDefaultAction(const BrowserAccessibility& node);
+
+  // Retrieve the bounds of the parent View in screen coordinates.
+  gfx::Rect GetViewBounds();
+
+  // Called when the renderer process has notified us of about tree changes.
+  // Send a notification to MSAA clients of the change.
+  void OnAccessibilityNotifications(
+      const std::vector<ViewHostMsg_AccessibilityNotification_Params>& params);
+
+  gfx::NativeView GetParentView();
+
+#if defined(OS_WIN)
+  BrowserAccessibilityManagerWin* toBrowserAccessibilityManagerWin();
+#endif
+
+  // Return the object that has focus, if it's a descandant of the
+  // given root (inclusive). Does not make a new reference.
+  BrowserAccessibility* GetFocus(BrowserAccessibility* root);
+
+ protected:
+  BrowserAccessibilityManager(
+      gfx::NativeView parent_view,
+      const WebAccessibility& src,
+      BrowserAccessibilityDelegate* delegate,
+      BrowserAccessibilityFactory* factory);
+
+ private:
+  void OnAccessibilityObjectStateChange(
+      const WebAccessibility& acc_obj);
+  void OnAccessibilityObjectChildrenChange(
+      const WebAccessibility& acc_obj);
+  void OnAccessibilityObjectFocusChange(
+      const WebAccessibility& acc_obj);
+  void OnAccessibilityObjectLoadComplete(
+      const WebAccessibility& acc_obj);
+  void OnAccessibilityObjectValueChange(
+      const WebAccessibility& acc_obj);
+  void OnAccessibilityObjectTextChange(
+      const WebAccessibility& acc_obj);
+
+  // Update an accessibility node with an updated WebAccessibility node
+  // received from the renderer process. When |include_children| is true
+  // the node's children will also be updated, otherwise only the node
+  // itself is updated. Returns the updated node or NULL if no node was
+  // updated.
+  BrowserAccessibility* UpdateNode(
+      const WebAccessibility& src,
+      bool include_children);
+
+  // Recursively build a tree of BrowserAccessibility objects from
+  // the WebAccessibility tree received from the renderer process.
+  BrowserAccessibility* CreateAccessibilityTree(
+      BrowserAccessibility* parent,
+      const WebAccessibility& src,
+      int index_in_parent);
+
+ protected:
+  // The next unique id for a BrowserAccessibility instance.
+  static int32 next_child_id_;
+
+  // The parent view.
+  gfx::NativeView parent_view_;
+
+  // The object that can perform actions on our behalf.
+  BrowserAccessibilityDelegate* delegate_;
+
+  // Factory to create BrowserAccessibility objects (for dependency injection).
+  scoped_ptr<BrowserAccessibilityFactory> factory_;
+
+  // The root of the tree of IAccessible objects and the element that
+  // currently has focus, if any.
+  BrowserAccessibility* root_;
+  BrowserAccessibility* focus_;
+
+  // A mapping from the IDs of objects in the renderer, to the child IDs
+  // we use internally here.
+  base::hash_map<int32, int32> renderer_id_to_child_id_map_;
+
+  // A mapping from child IDs to BrowserAccessibility objects.
+  base::hash_map<int32, BrowserAccessibility*> child_id_map_;
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityManager);
+};
+
+#endif  // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_H_
diff --git a/content/browser/accessibility/browser_accessibility_manager_mac.h b/content/browser/accessibility/browser_accessibility_manager_mac.h
new file mode 100644
index 0000000..c7c5089
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_manager_mac.h
@@ -0,0 +1,31 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_MAC_H_
+#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_MAC_H_
+#pragma once
+
+#import <Cocoa/Cocoa.h>
+
+#include "content/browser/accessibility/browser_accessibility_manager.h"
+
+class BrowserAccessibilityManagerMac : public BrowserAccessibilityManager {
+ public:
+  // Implementation of BrowserAccessibilityManager.
+  virtual void NotifyAccessibilityEvent(int type, BrowserAccessibility* node);
+
+ private:
+  // This gives BrowserAccessibilityManager::Create access to the class
+  // constructor.
+  friend class BrowserAccessibilityManager;
+
+  BrowserAccessibilityManagerMac(gfx::NativeView parent_view,
+                                 const webkit_glue::WebAccessibility& src,
+                                 BrowserAccessibilityDelegate* delegate,
+                                 BrowserAccessibilityFactory* factory);
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityManagerMac);
+};
+
+#endif  // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_MAC_H_
diff --git a/content/browser/accessibility/browser_accessibility_manager_mac.mm b/content/browser/accessibility/browser_accessibility_manager_mac.mm
new file mode 100644
index 0000000..b5618fe3
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_manager_mac.mm
@@ -0,0 +1,63 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/accessibility/browser_accessibility_manager_mac.h"
+
+#import "base/logging.h"
+#import "content/browser/accessibility/browser_accessibility_cocoa.h"
+#include "content/common/view_messages.h"
+
+// static
+BrowserAccessibilityManager* BrowserAccessibilityManager::Create(
+    gfx::NativeView parent_view,
+    const WebAccessibility& src,
+    BrowserAccessibilityDelegate* delegate,
+    BrowserAccessibilityFactory* factory) {
+  return new BrowserAccessibilityManagerMac(
+      parent_view, src, delegate, factory);
+}
+
+BrowserAccessibilityManagerMac::BrowserAccessibilityManagerMac(
+    gfx::NativeView parent_window,
+    const webkit_glue::WebAccessibility& src,
+    BrowserAccessibilityDelegate* delegate,
+    BrowserAccessibilityFactory* factory)
+        : BrowserAccessibilityManager(parent_window, src, delegate, factory) {
+}
+
+void BrowserAccessibilityManagerMac::NotifyAccessibilityEvent(
+    int type,
+    BrowserAccessibility* node) {
+  // Refer to AXObjectCache.mm (webkit).
+  NSString* event_id = @"";
+  switch (type) {
+    case ViewHostMsg_AccessibilityNotification_Type::
+        NOTIFICATION_TYPE_CHECK_STATE_CHANGED:
+      // Does not exist on Mac.
+      return;
+    case ViewHostMsg_AccessibilityNotification_Type::
+        NOTIFICATION_TYPE_CHILDREN_CHANGED:
+      // TODO(dtseng): no clear equivalent on Mac.
+      return;
+    case ViewHostMsg_AccessibilityNotification_Type::
+        NOTIFICATION_TYPE_FOCUS_CHANGED:
+      event_id = NSAccessibilityFocusedUIElementChangedNotification;
+      break;
+    case ViewHostMsg_AccessibilityNotification_Type::
+        NOTIFICATION_TYPE_LOAD_COMPLETE:
+      event_id = @"AXLoadComplete";
+      break;
+    case ViewHostMsg_AccessibilityNotification_Type::
+        NOTIFICATION_TYPE_VALUE_CHANGED:
+      event_id = NSAccessibilityValueChangedNotification;
+      break;
+    case ViewHostMsg_AccessibilityNotification_Type::
+        NOTIFICATION_TYPE_SELECTED_TEXT_CHANGED:
+      event_id = NSAccessibilitySelectedTextChangedNotification;
+      break;
+  }
+  BrowserAccessibilityCocoa* native_node = node->toBrowserAccessibilityCocoa();
+  DCHECK(native_node);
+  NSAccessibilityPostNotification(native_node, event_id);
+}
diff --git a/content/browser/accessibility/browser_accessibility_manager_win.cc b/content/browser/accessibility/browser_accessibility_manager_win.cc
new file mode 100644
index 0000000..7b992e7
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_manager_win.cc
@@ -0,0 +1,90 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/accessibility/browser_accessibility_manager_win.h"
+
+#include "content/browser/accessibility/browser_accessibility_win.h"
+#include "content/common/view_messages.h"
+
+using webkit_glue::WebAccessibility;
+
+// static
+BrowserAccessibilityManager* BrowserAccessibilityManager::Create(
+    gfx::NativeView parent_view,
+    const WebAccessibility& src,
+    BrowserAccessibilityDelegate* delegate,
+    BrowserAccessibilityFactory* factory) {
+  return new BrowserAccessibilityManagerWin(
+      parent_view,
+      src,
+      delegate,
+      factory);
+}
+
+BrowserAccessibilityManagerWin*
+BrowserAccessibilityManager::toBrowserAccessibilityManagerWin() {
+  return static_cast<BrowserAccessibilityManagerWin*>(this);
+}
+
+BrowserAccessibilityManagerWin::BrowserAccessibilityManagerWin(
+    HWND parent_view,
+    const WebAccessibility& src,
+    BrowserAccessibilityDelegate* delegate,
+    BrowserAccessibilityFactory* factory)
+    : BrowserAccessibilityManager(parent_view, src, delegate, factory) {
+  // Allow NULL parent_view for unit testing.
+  if (parent_view == NULL) {
+    window_iaccessible_ = NULL;
+    return;
+  }
+
+  HRESULT hr = ::CreateStdAccessibleObject(
+      parent_view, OBJID_WINDOW, IID_IAccessible,
+      reinterpret_cast<void **>(&window_iaccessible_));
+  DCHECK(SUCCEEDED(hr));
+}
+
+BrowserAccessibilityManagerWin::~BrowserAccessibilityManagerWin() {
+}
+
+IAccessible* BrowserAccessibilityManagerWin::GetParentWindowIAccessible() {
+  return window_iaccessible_;
+}
+
+void BrowserAccessibilityManagerWin::NotifyAccessibilityEvent(
+    int type,
+    BrowserAccessibility* node) {
+  LONG event_id = EVENT_MIN;
+  switch (type) {
+    case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_CHECK_STATE_CHANGED:
+      event_id = EVENT_OBJECT_STATECHANGE;
+      break;
+    case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_CHILDREN_CHANGED:
+      event_id = EVENT_OBJECT_REORDER;
+      break;
+    case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_FOCUS_CHANGED:
+      event_id = EVENT_OBJECT_FOCUS;
+      break;
+    case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_LOAD_COMPLETE:
+      event_id = IA2_EVENT_DOCUMENT_LOAD_COMPLETE;
+      break;
+    case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_VALUE_CHANGED:
+      event_id = EVENT_OBJECT_VALUECHANGE;
+      break;
+    case ViewHostMsg_AccessibilityNotification_Type::
+          NOTIFICATION_TYPE_SELECTED_TEXT_CHANGED:
+      event_id = IA2_EVENT_TEXT_CARET_MOVED;
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
+
+  NotifyWinEvent(event_id, GetParentView(), OBJID_CLIENT, node->child_id());
+}
diff --git a/content/browser/accessibility/browser_accessibility_manager_win.h b/content/browser/accessibility/browser_accessibility_manager_win.h
new file mode 100644
index 0000000..04ea53f
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_manager_win.h
@@ -0,0 +1,48 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_WIN_H_
+#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_WIN_H_
+#pragma once
+
+#include <oleacc.h>
+
+#include "base/win/scoped_comptr.h"
+#include "content/browser/accessibility/browser_accessibility_manager.h"
+#include "webkit/glue/webaccessibility.h"
+
+class BrowserAccessibilityWin;
+struct ViewHostMsg_AccessibilityNotification_Params;
+
+using webkit_glue::WebAccessibility;
+
+// Manages a tree of BrowserAccessibilityWin objects.
+class BrowserAccessibilityManagerWin : public BrowserAccessibilityManager {
+ public:
+  virtual ~BrowserAccessibilityManagerWin();
+
+  // Get a the default IAccessible for the parent window, does not make a
+  // new reference.
+  IAccessible* GetParentWindowIAccessible();
+
+  // BrowserAccessibilityManager methods
+  virtual void NotifyAccessibilityEvent(int type, BrowserAccessibility* node);
+
+ private:
+  BrowserAccessibilityManagerWin(
+      HWND parent_window,
+      const WebAccessibility& src,
+      BrowserAccessibilityDelegate* delegate,
+      BrowserAccessibilityFactory* factory);
+
+  // A default IAccessible instance for the parent window.
+  base::win::ScopedComPtr<IAccessible> window_iaccessible_;
+
+  // Give BrowserAccessibilityManager::Create access to our constructor.
+  friend class BrowserAccessibilityManager;
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityManagerWin);
+};
+
+#endif  // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_WIN_H_
diff --git a/content/browser/accessibility/browser_accessibility_state.cc b/content/browser/accessibility/browser_accessibility_state.cc
new file mode 100644
index 0000000..45b3a3b
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_state.cc
@@ -0,0 +1,27 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/accessibility/browser_accessibility_state.h"
+
+#include "base/memory/singleton.h"
+
+BrowserAccessibilityState::BrowserAccessibilityState()
+    : screen_reader_active_(false) {
+}
+
+BrowserAccessibilityState::~BrowserAccessibilityState() {
+}
+
+// static
+BrowserAccessibilityState* BrowserAccessibilityState::GetInstance() {
+  return Singleton<BrowserAccessibilityState>::get();
+}
+
+void BrowserAccessibilityState::OnScreenReaderDetected() {
+  screen_reader_active_ = true;
+}
+
+bool BrowserAccessibilityState::IsAccessibleBrowser() {
+  return screen_reader_active_;
+}
diff --git a/content/browser/accessibility/browser_accessibility_state.h b/content/browser/accessibility/browser_accessibility_state.h
new file mode 100644
index 0000000..82cb8a3
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_state.h
@@ -0,0 +1,53 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_STATE_H_
+#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_STATE_H_
+#pragma once
+
+#include "base/basictypes.h"
+
+template <typename T> struct DefaultSingletonTraits;
+
+// The BrowserAccessibilityState class is used to determine if Chrome should be
+// customized for users with assistive technology, such as screen readers. We
+// modify the behavior of certain user interfaces to provide a better experience
+// for screen reader users. The way we detect a screen reader program is
+// different for each platform.
+//
+// Screen Reader Detection
+// (1) On windows many screen reader detection mechinisms will give false
+// positives like relying on the SPI_GETSCREENREADER system parameter. In Chrome
+// we attempt to dynamically detect a MSAA client screen reader by calling
+// NotifiyWinEvent in NativeWidgetWin with a custom ID and wait to see if the ID
+// is requested by a subsequent call to WM_GETOBJECT.
+// (2) On mac we detect dynamically if VoiceOver is running.  We rely upon the
+// undocumented accessibility attribute @"AXEnhancedUserInterface" which is set
+// when VoiceOver is launched and unset when VoiceOver is closed.  This is an
+// improvement over reading defaults preference values (which has no callback
+// mechanism).
+class BrowserAccessibilityState {
+ public:
+  // Returns the singleton instance.
+  static BrowserAccessibilityState* GetInstance();
+
+  ~BrowserAccessibilityState();
+
+  // Called when screen reader client is detected.
+  void OnScreenReaderDetected();
+
+  // Returns true if the browser should be customized for accessibility.
+  bool IsAccessibleBrowser();
+
+ private:
+  BrowserAccessibilityState();
+  friend struct DefaultSingletonTraits<BrowserAccessibilityState>;
+
+  // Set to true when a screen reader client is detected.
+  bool screen_reader_active_;
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityState);
+};
+
+#endif  // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_STATE_H_
diff --git a/content/browser/accessibility/browser_accessibility_win.cc b/content/browser/accessibility/browser_accessibility_win.cc
new file mode 100644
index 0000000..8cd1566
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_win.cc
@@ -0,0 +1,1634 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/accessibility/browser_accessibility_win.h"
+
+#include "base/string_number_conversions.h"
+#include "base/string_util.h"
+#include "base/utf_string_conversions.h"
+#include "content/browser/accessibility/browser_accessibility_manager_win.h"
+#include "net/base/escape.h"
+
+using webkit_glue::WebAccessibility;
+
+// The GUID for the ISimpleDOM service is not defined in the IDL files.
+// This is taken directly from the Mozilla sources
+// (accessible/src/msaa/nsAccessNodeWrap.cpp) and it's also documented at:
+// http://developer.mozilla.org/en/Accessibility/AT-APIs/ImplementationFeatures/MSAA
+
+const GUID GUID_ISimpleDOM = {
+    0x0c539790, 0x12e4, 0x11cf,
+    0xb6, 0x61, 0x00, 0xaa, 0x00, 0x4c, 0xd6, 0xd8};
+
+// static
+BrowserAccessibility* BrowserAccessibility::Create() {
+  CComObject<BrowserAccessibilityWin>* instance;
+  HRESULT hr = CComObject<BrowserAccessibilityWin>::CreateInstance(&instance);
+  DCHECK(SUCCEEDED(hr));
+  return instance->NewReference();
+}
+
+BrowserAccessibilityWin* BrowserAccessibility::toBrowserAccessibilityWin() {
+  return static_cast<BrowserAccessibilityWin*>(this);
+}
+
+BrowserAccessibilityWin::BrowserAccessibilityWin()
+    : ia_role_(0),
+      ia_state_(0),
+      ia2_role_(0),
+      ia2_state_(0) {
+}
+
+BrowserAccessibilityWin::~BrowserAccessibilityWin() {
+}
+
+//
+// IAccessible methods.
+//
+// Conventions:
+// * Always test for instance_active_ first and return E_FAIL if it's false.
+// * Always check for invalid arguments first, even if they're unused.
+// * Return S_FALSE if the only output is a string argument and it's empty.
+//
+
+HRESULT BrowserAccessibilityWin::accDoDefaultAction(VARIANT var_id) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_id);
+  if (!target)
+    return E_INVALIDARG;
+
+  manager_->DoDefaultAction(*target);
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::accHitTest(LONG x_left,
+                                                 LONG y_top,
+                                                 VARIANT* child) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!child)
+    return E_INVALIDARG;
+
+  gfx::Point point(x_left, y_top);
+  if (!GetBoundsRect().Contains(point)) {
+    // Return S_FALSE and VT_EMPTY when the outside the object's boundaries.
+    child->vt = VT_EMPTY;
+    return S_FALSE;
+  }
+
+  BrowserAccessibility* result = BrowserAccessibilityForPoint(point);
+  if (result == this) {
+    // Point is within this object.
+    child->vt = VT_I4;
+    child->lVal = CHILDID_SELF;
+  } else {
+    child->vt = VT_DISPATCH;
+    child->pdispVal = result->toBrowserAccessibilityWin()->NewReference();
+  }
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::accLocation(LONG* x_left, LONG* y_top,
+                                                  LONG* width, LONG* height,
+                                                  VARIANT var_id) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!x_left || !y_top || !width || !height)
+    return E_INVALIDARG;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_id);
+  if (!target)
+    return E_INVALIDARG;
+
+  gfx::Rect bounds = target->GetBoundsRect();
+  *x_left = bounds.x();
+  *y_top  = bounds.y();
+  *width  = bounds.width();
+  *height = bounds.height();
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::accNavigate(
+    LONG nav_dir, VARIANT start, VARIANT* end) {
+  BrowserAccessibilityWin* target = GetTargetFromChildID(start);
+  if (!target)
+    return E_INVALIDARG;
+
+  if ((nav_dir == NAVDIR_LASTCHILD || nav_dir == NAVDIR_FIRSTCHILD) &&
+      start.lVal != CHILDID_SELF) {
+    // MSAA states that navigating to first/last child can only be from self.
+    return E_INVALIDARG;
+  }
+
+  BrowserAccessibility* result = NULL;
+  switch (nav_dir) {
+    case NAVDIR_DOWN:
+    case NAVDIR_UP:
+    case NAVDIR_LEFT:
+    case NAVDIR_RIGHT:
+      // These directions are not implemented, matching Mozilla and IE.
+      return E_NOTIMPL;
+    case NAVDIR_FIRSTCHILD:
+      if (!target->children_.empty())
+        result = target->children_.front();
+      break;
+    case NAVDIR_LASTCHILD:
+      if (!target->children_.empty())
+        result = target->children_.back();
+      break;
+    case NAVDIR_NEXT:
+      result = target->GetNextSibling();
+      break;
+    case NAVDIR_PREVIOUS:
+      result = target->GetPreviousSibling();
+      break;
+  }
+
+  if (!result) {
+    end->vt = VT_EMPTY;
+    return S_FALSE;
+  }
+
+  end->vt = VT_DISPATCH;
+  end->pdispVal = result->toBrowserAccessibilityWin()->NewReference();
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accChild(VARIANT var_child,
+                                                   IDispatch** disp_child) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!disp_child)
+    return E_INVALIDARG;
+
+  *disp_child = NULL;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_child);
+  if (!target)
+    return E_INVALIDARG;
+
+  (*disp_child) = target->NewReference();
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accChildCount(LONG* child_count) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!child_count)
+    return E_INVALIDARG;
+
+  *child_count = children_.size();
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accDefaultAction(VARIANT var_id,
+                                                           BSTR* def_action) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!def_action)
+    return E_INVALIDARG;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_id);
+  if (!target)
+    return E_INVALIDARG;
+
+  return target->GetAttributeAsBstr(
+      WebAccessibility::ATTR_SHORTCUT, def_action);
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accDescription(VARIANT var_id,
+                                                         BSTR* desc) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!desc)
+    return E_INVALIDARG;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_id);
+  if (!target)
+    return E_INVALIDARG;
+
+  return target->GetAttributeAsBstr(WebAccessibility::ATTR_DESCRIPTION, desc);
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accFocus(VARIANT* focus_child) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!focus_child)
+    return E_INVALIDARG;
+
+  BrowserAccessibilityWin* focus = static_cast<BrowserAccessibilityWin*>(
+      manager_->GetFocus(this));
+  if (focus == this) {
+    focus_child->vt = VT_I4;
+    focus_child->lVal = CHILDID_SELF;
+  } else if (focus == NULL) {
+    focus_child->vt = VT_EMPTY;
+  } else {
+    focus_child->vt = VT_DISPATCH;
+    focus_child->pdispVal = focus->NewReference();
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accHelp(VARIANT var_id, BSTR* help) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!help)
+    return E_INVALIDARG;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_id);
+  if (!target)
+    return E_INVALIDARG;
+
+  return target->GetAttributeAsBstr(WebAccessibility::ATTR_HELP, help);
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accKeyboardShortcut(VARIANT var_id,
+                                                              BSTR* acc_key) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!acc_key)
+    return E_INVALIDARG;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_id);
+  if (!target)
+    return E_INVALIDARG;
+
+  return target->GetAttributeAsBstr(WebAccessibility::ATTR_SHORTCUT, acc_key);
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accName(VARIANT var_id, BSTR* name) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!name)
+    return E_INVALIDARG;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_id);
+  if (!target)
+    return E_INVALIDARG;
+
+  if (target->name_.empty())
+    return S_FALSE;
+
+  *name = SysAllocString(target->name_.c_str());
+
+  DCHECK(*name);
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accParent(IDispatch** disp_parent) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!disp_parent)
+    return E_INVALIDARG;
+
+  IAccessible* parent = parent_->toBrowserAccessibilityWin();
+  if (parent == NULL) {
+    // This happens if we're the root of the tree;
+    // return the IAccessible for the window.
+    parent = manager_->toBrowserAccessibilityManagerWin()->
+             GetParentWindowIAccessible();
+  }
+
+  parent->AddRef();
+  *disp_parent = parent;
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accRole(
+    VARIANT var_id, VARIANT* role) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!role)
+    return E_INVALIDARG;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_id);
+  if (!target)
+    return E_INVALIDARG;
+
+  if (!target->role_name_.empty()) {
+    role->vt = VT_BSTR;
+    role->bstrVal = SysAllocString(target->role_name_.c_str());
+  } else {
+    role->vt = VT_I4;
+    role->lVal = target->ia_role_;
+  }
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accState(VARIANT var_id,
+                                                   VARIANT* state) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!state)
+    return E_INVALIDARG;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_id);
+  if (!target)
+    return E_INVALIDARG;
+
+  state->vt = VT_I4;
+  state->lVal = target->ia_state_;
+  if (manager_->GetFocus(NULL) == this)
+    state->lVal |= STATE_SYSTEM_FOCUSED;
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accValue(
+    VARIANT var_id, BSTR* value) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!value)
+    return E_INVALIDARG;
+
+  BrowserAccessibilityWin* target = GetTargetFromChildID(var_id);
+  if (!target)
+    return E_INVALIDARG;
+
+  *value = SysAllocString(target->value_.c_str());
+
+  DCHECK(*value);
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accHelpTopic(
+    BSTR* help_file, VARIANT var_id, LONG* topic_id) {
+  return E_NOTIMPL;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_accSelection(VARIANT* selected) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  return E_NOTIMPL;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::accSelect(
+    LONG flags_sel, VARIANT var_id) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (flags_sel & SELFLAG_TAKEFOCUS) {
+    manager_->SetFocus(this, true);
+    return S_OK;
+  }
+
+  return S_FALSE;
+}
+
+//
+// IAccessible2 methods.
+//
+
+STDMETHODIMP BrowserAccessibilityWin::role(LONG* role) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!role)
+    return E_INVALIDARG;
+
+  *role = ia2_role_;
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_attributes(BSTR* attributes) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!attributes)
+    return E_INVALIDARG;
+
+  // Follow Firefox's convention, which is to return a set of key-value pairs
+  // separated by semicolons, with a colon between the key and the value.
+  string16 str;
+  for (unsigned int i = 0; i < html_attributes_.size(); i++) {
+    if (i != 0)
+      str += L';';
+    str += Escape(html_attributes_[i].first);
+    str += L':';
+    str += Escape(html_attributes_[i].second);
+  }
+
+  if (str.empty())
+    return S_FALSE;
+
+  *attributes = SysAllocString(str.c_str());
+  DCHECK(*attributes);
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_states(AccessibleStates* states) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!states)
+    return E_INVALIDARG;
+
+  *states = ia2_state_;
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_uniqueID(LONG* unique_id) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!unique_id)
+    return E_INVALIDARG;
+
+  *unique_id = child_id_;
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_windowHandle(HWND* window_handle) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!window_handle)
+    return E_INVALIDARG;
+
+  *window_handle = manager_->GetParentView();
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_indexInParent(LONG* index_in_parent) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!index_in_parent)
+    return E_INVALIDARG;
+
+  *index_in_parent = index_in_parent_;
+  return S_OK;
+}
+
+//
+// IAccessibleImage methods.
+//
+
+STDMETHODIMP BrowserAccessibilityWin::get_description(BSTR* desc) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!desc)
+    return E_INVALIDARG;
+
+  return GetAttributeAsBstr(WebAccessibility::ATTR_DESCRIPTION, desc);
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_imagePosition(
+    enum IA2CoordinateType coordinate_type, LONG* x, LONG* y) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!x || !y)
+    return E_INVALIDARG;
+
+  if (coordinate_type == IA2_COORDTYPE_SCREEN_RELATIVE) {
+    HWND parent_hwnd = manager_->GetParentView();
+    POINT top_left = {0, 0};
+    ::ClientToScreen(parent_hwnd, &top_left);
+    *x = location_.x() + top_left.x;
+    *y = location_.y() + top_left.y;
+  } else if (coordinate_type == IA2_COORDTYPE_PARENT_RELATIVE) {
+    *x = location_.x();
+    *y = location_.y();
+    if (parent_) {
+      *x -= parent_->location().x();
+      *y -= parent_->location().y();
+    }
+  } else {
+    return E_INVALIDARG;
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_imageSize(LONG* height, LONG* width) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!height || !width)
+    return E_INVALIDARG;
+
+  *height = location_.height();
+  *width = location_.width();
+  return S_OK;
+}
+
+//
+// IAccessibleText methods.
+//
+
+STDMETHODIMP BrowserAccessibilityWin::get_nCharacters(LONG* n_characters) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!n_characters)
+    return E_INVALIDARG;
+
+  if (role_ == WebAccessibility::ROLE_TEXT_FIELD ||
+      role_ == WebAccessibility::ROLE_TEXTAREA) {
+    *n_characters = value_.length();
+  } else {
+    *n_characters = name_.length();
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_caretOffset(LONG* offset) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!offset)
+    return E_INVALIDARG;
+
+  if (role_ == WebAccessibility::ROLE_TEXT_FIELD ||
+      role_ == WebAccessibility::ROLE_TEXTAREA) {
+    int sel_start = 0;
+    if (GetAttributeAsInt(WebAccessibility::ATTR_TEXT_SEL_START, &sel_start)) {
+      *offset = sel_start;
+    } else {
+      *offset = 0;
+    }
+  } else {
+    *offset = 0;
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_nSelections(LONG* n_selections) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!n_selections)
+    return E_INVALIDARG;
+
+  if (role_ == WebAccessibility::ROLE_TEXT_FIELD ||
+      role_ == WebAccessibility::ROLE_TEXTAREA) {
+    int sel_start = 0;
+    int sel_end = 0;
+    if (GetAttributeAsInt(WebAccessibility::ATTR_TEXT_SEL_START, &sel_start) &&
+        GetAttributeAsInt(WebAccessibility::ATTR_TEXT_SEL_END, &sel_end) &&
+        sel_start != sel_end) {
+      *n_selections = 1;
+    } else {
+      *n_selections = 0;
+    }
+  } else {
+    *n_selections = 0;
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_selection(LONG selection_index,
+                                                    LONG* start_offset,
+                                                    LONG* end_offset) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!start_offset || !end_offset || selection_index != 0)
+    return E_INVALIDARG;
+
+  if (role_ == WebAccessibility::ROLE_TEXT_FIELD ||
+      role_ == WebAccessibility::ROLE_TEXTAREA) {
+    int sel_start = 0;
+    int sel_end = 0;
+    if (GetAttributeAsInt(WebAccessibility::ATTR_TEXT_SEL_START, &sel_start) &&
+        GetAttributeAsInt(WebAccessibility::ATTR_TEXT_SEL_END, &sel_end)) {
+      *start_offset = sel_start;
+      *end_offset = sel_end;
+    } else {
+      *start_offset = 0;
+      *end_offset = 0;
+    }
+  } else {
+    *start_offset = 0;
+    *end_offset = 0;
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_text(
+    LONG start_offset, LONG end_offset, BSTR* text) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!text)
+    return E_INVALIDARG;
+
+  const string16& text_str = TextForIAccessibleText();
+
+  // Handle special text offsets.
+  HandleSpecialTextOffset(text_str, &start_offset);
+  HandleSpecialTextOffset(text_str, &end_offset);
+
+  // The spec allows the arguments to be reversed.
+  if (start_offset > end_offset) {
+    LONG tmp = start_offset;
+    start_offset = end_offset;
+    end_offset = tmp;
+  }
+
+  // The spec does not allow the start or end offsets to be out or range;
+  // we must return an error if so.
+  LONG len = text_str.length();
+  if (start_offset < 0)
+    return E_INVALIDARG;
+  if (end_offset > len)
+    return E_INVALIDARG;
+
+  string16 substr = text_str.substr(start_offset, end_offset - start_offset);
+  if (substr.empty())
+    return S_FALSE;
+
+  *text = SysAllocString(substr.c_str());
+  DCHECK(*text);
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_textAtOffset(
+    LONG offset,
+    enum IA2TextBoundaryType boundary_type,
+    LONG* start_offset, LONG* end_offset,
+    BSTR* text) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!start_offset || !end_offset || !text)
+    return E_INVALIDARG;
+
+  // The IAccessible2 spec says we don't have to implement the "sentence"
+  // boundary type, we can just let the screenreader handle it.
+  if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
+    *start_offset = 0;
+    *end_offset = 0;
+    *text = NULL;
+    return S_FALSE;
+  }
+
+  const string16& text_str = TextForIAccessibleText();
+
+  *start_offset = FindBoundary(text_str, boundary_type, offset, -1);
+  *end_offset = FindBoundary(text_str, boundary_type, offset, 1);
+  return get_text(*start_offset, *end_offset, text);
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_textBeforeOffset(
+    LONG offset,
+    enum IA2TextBoundaryType boundary_type,
+    LONG* start_offset, LONG* end_offset,
+    BSTR* text) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!start_offset || !end_offset || !text)
+    return E_INVALIDARG;
+
+  // The IAccessible2 spec says we don't have to implement the "sentence"
+  // boundary type, we can just let the screenreader handle it.
+  if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
+    *start_offset = 0;
+    *end_offset = 0;
+    *text = NULL;
+    return S_FALSE;
+  }
+
+  const string16& text_str = TextForIAccessibleText();
+
+  *start_offset = FindBoundary(text_str, boundary_type, offset, -1);
+  *end_offset = offset;
+  return get_text(*start_offset, *end_offset, text);
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_textAfterOffset(
+    LONG offset,
+    enum IA2TextBoundaryType boundary_type,
+    LONG* start_offset, LONG* end_offset,
+    BSTR* text) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!start_offset || !end_offset || !text)
+    return E_INVALIDARG;
+
+  // The IAccessible2 spec says we don't have to implement the "sentence"
+  // boundary type, we can just let the screenreader handle it.
+  if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
+    *start_offset = 0;
+    *end_offset = 0;
+    *text = NULL;
+    return S_FALSE;
+  }
+
+  const string16& text_str = TextForIAccessibleText();
+
+  *start_offset = offset;
+  *end_offset = FindBoundary(text_str, boundary_type, offset, 1);
+  return get_text(*start_offset, *end_offset, text);
+}
+
+//
+// ISimpleDOMDocument methods.
+//
+
+STDMETHODIMP BrowserAccessibilityWin::get_URL(BSTR* url) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!url)
+    return E_INVALIDARG;
+
+  return GetAttributeAsBstr(WebAccessibility::ATTR_DOC_URL, url);
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_title(BSTR* title) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!title)
+    return E_INVALIDARG;
+
+  return GetAttributeAsBstr(WebAccessibility::ATTR_DOC_TITLE, title);
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_mimeType(BSTR* mime_type) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!mime_type)
+    return E_INVALIDARG;
+
+  return GetAttributeAsBstr(WebAccessibility::ATTR_DOC_MIMETYPE, mime_type);
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_docType(BSTR* doc_type) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!doc_type)
+    return E_INVALIDARG;
+
+  return GetAttributeAsBstr(WebAccessibility::ATTR_DOC_DOCTYPE, doc_type);
+}
+
+//
+// ISimpleDOMNode methods.
+//
+
+STDMETHODIMP BrowserAccessibilityWin::get_nodeInfo(
+    BSTR* node_name,
+    short* name_space_id,
+    BSTR* node_value,
+    unsigned int* num_children,
+    unsigned int* unique_id,
+    unsigned short* node_type) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!node_name || !name_space_id || !node_value || !num_children ||
+      !unique_id || !node_type) {
+    return E_INVALIDARG;
+  }
+
+  string16 tag;
+  if (GetAttribute(WebAccessibility::ATTR_HTML_TAG, &tag))
+    *node_name = SysAllocString(tag.c_str());
+  else
+    *node_name = NULL;
+
+  *name_space_id = 0;
+  *node_value = SysAllocString(value_.c_str());
+  *num_children = children_.size();
+  *unique_id = child_id_;
+
+  if (ia_role_ == ROLE_SYSTEM_DOCUMENT) {
+    *node_type = NODETYPE_DOCUMENT;
+  } else if (ia_role_ == ROLE_SYSTEM_TEXT &&
+             ((ia2_state_ & IA2_STATE_EDITABLE) == 0)) {
+    *node_type = NODETYPE_TEXT;
+  } else {
+    *node_type = NODETYPE_ELEMENT;
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_attributes(
+    unsigned short max_attribs,
+    BSTR* attrib_names,
+    short* name_space_id,
+    BSTR* attrib_values,
+    unsigned short* num_attribs) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!attrib_names || !name_space_id || !attrib_values || !num_attribs)
+    return E_INVALIDARG;
+
+  *num_attribs = max_attribs;
+  if (*num_attribs > html_attributes_.size())
+    *num_attribs = html_attributes_.size();
+
+  for (unsigned short i = 0; i < *num_attribs; ++i) {
+    attrib_names[i] = SysAllocString(html_attributes_[i].first.c_str());
+    name_space_id[i] = 0;
+    attrib_values[i] = SysAllocString(html_attributes_[i].second.c_str());
+  }
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_attributesForNames(
+    unsigned short num_attribs,
+    BSTR* attrib_names,
+    short* name_space_id,
+    BSTR* attrib_values) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!attrib_names || !name_space_id || !attrib_values)
+    return E_INVALIDARG;
+
+  for (unsigned short i = 0; i < num_attribs; ++i) {
+    name_space_id[i] = 0;
+    bool found = false;
+    string16 name = (LPCWSTR)attrib_names[i];
+    for (unsigned int j = 0;  j < html_attributes_.size(); ++j) {
+      if (html_attributes_[j].first == name) {
+        attrib_values[i] = SysAllocString(html_attributes_[j].second.c_str());
+        found = true;
+        break;
+      }
+    }
+    if (!found) {
+      attrib_values[i] = NULL;
+    }
+  }
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_computedStyle(
+    unsigned short max_style_properties,
+    boolean use_alternate_view,
+    BSTR *style_properties,
+    BSTR *style_values,
+    unsigned short *num_style_properties)  {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!style_properties || !style_values)
+    return E_INVALIDARG;
+
+  // We only cache a single style property for now: DISPLAY
+
+  if (max_style_properties == 0 ||
+      !HasAttribute(WebAccessibility::ATTR_DISPLAY)) {
+    *num_style_properties = 0;
+    return S_OK;
+  }
+
+  string16 display;
+  GetAttribute(WebAccessibility::ATTR_DISPLAY, &display);
+  *num_style_properties = 1;
+  style_properties[0] = SysAllocString(L"display");
+  style_values[0] = SysAllocString(display.c_str());
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_computedStyleForProperties(
+    unsigned short num_style_properties,
+    boolean use_alternate_view,
+    BSTR* style_properties,
+    BSTR* style_values) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!style_properties || !style_values)
+    return E_INVALIDARG;
+
+  // We only cache a single style property for now: DISPLAY
+
+  for (unsigned short i = 0; i < num_style_properties; i++) {
+    string16 name = (LPCWSTR)style_properties[i];
+    StringToLowerASCII(&name);
+    if (name == L"display") {
+      string16 display;
+      GetAttribute(WebAccessibility::ATTR_DISPLAY, &display);
+      style_values[i] = SysAllocString(display.c_str());
+    } else {
+      style_values[i] = NULL;
+    }
+  }
+
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::scrollTo(boolean placeTopLeft) {
+  return E_NOTIMPL;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_parentNode(ISimpleDOMNode** node) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!node)
+    return E_INVALIDARG;
+
+  *node = parent_->toBrowserAccessibilityWin()->NewReference();
+  return S_OK;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_firstChild(ISimpleDOMNode** node)  {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!node)
+    return E_INVALIDARG;
+
+  if (children_.size()) {
+    *node = children_[0]->toBrowserAccessibilityWin()->NewReference();
+    return S_OK;
+  } else {
+    *node = NULL;
+    return S_FALSE;
+  }
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_lastChild(ISimpleDOMNode** node) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!node)
+    return E_INVALIDARG;
+
+  if (children_.size()) {
+    *node = children_[children_.size() - 1]->toBrowserAccessibilityWin()->
+        NewReference();
+    return S_OK;
+  } else {
+    *node = NULL;
+    return S_FALSE;
+  }
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_previousSibling(
+    ISimpleDOMNode** node) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!node)
+    return E_INVALIDARG;
+
+  if (parent_ && index_in_parent_ > 0) {
+    *node = parent_->children()[index_in_parent_ - 1]->
+        toBrowserAccessibilityWin()->NewReference();
+    return S_OK;
+  } else {
+    *node = NULL;
+    return S_FALSE;
+  }
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_nextSibling(ISimpleDOMNode** node) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!node)
+    return E_INVALIDARG;
+
+  if (parent_ &&
+      index_in_parent_ >= 0 &&
+      index_in_parent_ < static_cast<int>(parent_->children().size()) - 1) {
+    *node = parent_->children()[index_in_parent_ + 1]->
+        toBrowserAccessibilityWin()->NewReference();
+    return S_OK;
+  } else {
+    *node = NULL;
+    return S_FALSE;
+  }
+}
+
+STDMETHODIMP BrowserAccessibilityWin::get_childAt(
+    unsigned int child_index,
+    ISimpleDOMNode** node) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!node)
+    return E_INVALIDARG;
+
+  if (child_index < children_.size()) {
+    *node = children_[child_index]->toBrowserAccessibilityWin()->NewReference();
+    return S_OK;
+  } else {
+    *node = NULL;
+    return S_FALSE;
+  }
+}
+
+//
+// ISimpleDOMText methods.
+//
+
+STDMETHODIMP BrowserAccessibilityWin::get_domText(BSTR* dom_text) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (!dom_text)
+    return E_INVALIDARG;
+
+  if (name_.empty())
+    return S_FALSE;
+
+  *dom_text = SysAllocString(name_.c_str());
+  DCHECK(*dom_text);
+  return S_OK;
+}
+
+//
+// IServiceProvider methods.
+//
+
+STDMETHODIMP BrowserAccessibilityWin::QueryService(
+    REFGUID guidService, REFIID riid, void** object) {
+  if (!instance_active_)
+    return E_FAIL;
+
+  if (guidService == IID_IAccessible ||
+      guidService == IID_IAccessible2 ||
+      guidService == IID_IAccessibleImage ||
+      guidService == IID_IAccessibleText ||
+      guidService == IID_ISimpleDOMDocument ||
+      guidService == IID_ISimpleDOMNode ||
+      guidService == IID_ISimpleDOMText ||
+      guidService == GUID_ISimpleDOM) {
+    return QueryInterface(riid, object);
+  }
+
+  *object = NULL;
+  return E_FAIL;
+}
+
+//
+// CComObjectRootEx methods.
+//
+
+HRESULT WINAPI BrowserAccessibilityWin::InternalQueryInterface(
+    void* this_ptr,
+    const _ATL_INTMAP_ENTRY* entries,
+    REFIID iid,
+    void** object) {
+  if (iid == IID_IAccessibleText) {
+    if (ia_role_ != ROLE_SYSTEM_LINK && ia_role_ != ROLE_SYSTEM_TEXT) {
+      *object = NULL;
+      return E_NOINTERFACE;
+    }
+  } else if (iid == IID_IAccessibleImage) {
+    if (ia_role_ != ROLE_SYSTEM_GRAPHIC) {
+      *object = NULL;
+      return E_NOINTERFACE;
+    }
+  } else if (iid == IID_ISimpleDOMDocument) {
+    if (ia_role_ != ROLE_SYSTEM_DOCUMENT) {
+      *object = NULL;
+      return E_NOINTERFACE;
+    }
+  }
+
+  return CComObjectRootBase::InternalQueryInterface(
+      this_ptr, entries, iid, object);
+}
+
+//
+// Private methods.
+//
+
+// Initialize this object and mark it as active.
+void BrowserAccessibilityWin::Initialize() {
+  BrowserAccessibility::Initialize();
+
+  InitRoleAndState();
+
+  // Expose headings levels to NVDA with the "level" object attribute.
+  if (role_ == WebAccessibility::ROLE_HEADING && role_name_.size() == 2 &&
+          IsAsciiDigit(role_name_[1])) {
+    html_attributes_.push_back(std::make_pair(L"level", role_name_.substr(1)));
+  }
+
+  // Expose the "display" object attribute.
+  string16 display;
+  if (GetAttribute(WebAccessibility::ATTR_DISPLAY, &display))
+    html_attributes_.push_back(std::make_pair(L"display", display));
+
+  // If this is static text, put the text in the name rather than the value.
+  if (role_ == WebAccessibility::ROLE_STATIC_TEXT && name_.empty())
+    name_.swap(value_);
+
+  // If this object doesn't have a name but it does have a description,
+  // use the description as its name - because some screen readers only
+  // announce the name.
+  if (name_.empty() && HasAttribute(WebAccessibility::ATTR_DESCRIPTION))
+    GetAttribute(WebAccessibility::ATTR_DESCRIPTION, &name_);
+
+  // If this doesn't have a value and is linked then set its value to the url
+  // attribute. This allows screen readers to read an empty link's destination.
+  if (value_.empty() && (ia_state_ & STATE_SYSTEM_LINKED) &&
+      HasAttribute(WebAccessibility::ATTR_URL)) {
+    GetAttribute(WebAccessibility::ATTR_URL, &value_);
+  }
+}
+
+void BrowserAccessibilityWin::NativeAddReference() {
+  AddRef();
+}
+
+void BrowserAccessibilityWin::NativeReleaseReference() {
+  Release();
+}
+
+BrowserAccessibilityWin* BrowserAccessibilityWin::NewReference() {
+  AddRef();
+  return this;
+}
+
+BrowserAccessibilityWin* BrowserAccessibilityWin::GetTargetFromChildID(
+    const VARIANT& var_id) {
+  if (var_id.vt != VT_I4)
+    return NULL;
+
+  LONG child_id = var_id.lVal;
+  if (child_id == CHILDID_SELF)
+    return this;
+
+  if (child_id >= 1 && child_id <= static_cast<LONG>(children_.size()))
+    return children_[child_id - 1]->toBrowserAccessibilityWin();
+
+  return manager_->GetFromChildID(child_id)->toBrowserAccessibilityWin();
+}
+
+HRESULT BrowserAccessibilityWin::GetAttributeAsBstr(
+    WebAccessibility::Attribute attribute, BSTR* value_bstr) {
+  string16 str;
+
+  if (!GetAttribute(attribute, &str))
+    return S_FALSE;
+
+  if (str.empty())
+    return S_FALSE;
+
+  *value_bstr = SysAllocString(str.c_str());
+  DCHECK(*value_bstr);
+
+  return S_OK;
+}
+
+string16 BrowserAccessibilityWin::Escape(const string16& str) {
+  return EscapeQueryParamValueUTF8(str, false);
+}
+
+const string16& BrowserAccessibilityWin::TextForIAccessibleText() {
+  if (role_ == WebAccessibility::ROLE_TEXT_FIELD ||
+      role_ == WebAccessibility::ROLE_TEXTAREA) {
+    return value_;
+  } else {
+    return name_;
+  }
+}
+
+void BrowserAccessibilityWin::HandleSpecialTextOffset(
+    const string16& text, LONG* offset) {
+  if (*offset == IA2_TEXT_OFFSET_LENGTH) {
+    *offset = static_cast<LONG>(text.size());
+  } else if (*offset == IA2_TEXT_OFFSET_CARET) {
+    get_caretOffset(offset);
+  }
+}
+
+LONG BrowserAccessibilityWin::FindBoundary(
+    const string16& text,
+    IA2TextBoundaryType boundary,
+    LONG start_offset,
+    LONG direction) {
+  LONG text_size = static_cast<LONG>(text.size());
+  DCHECK((start_offset >= 0 && start_offset <= text_size) ||
+         start_offset == IA2_TEXT_OFFSET_LENGTH ||
+         start_offset == IA2_TEXT_OFFSET_CARET);
+  DCHECK(direction == 1 || direction == -1);
+
+  HandleSpecialTextOffset(text, &start_offset);
+
+  if (boundary == IA2_TEXT_BOUNDARY_CHAR) {
+    if (direction == 1 && start_offset < text_size)
+      return start_offset + 1;
+    else
+      return start_offset;
+  } else if (boundary == IA2_TEXT_BOUNDARY_LINE) {
+    if (direction == 1) {
+      for (int j = 0; j < static_cast<int>(line_breaks_.size()); j++) {
+        if (line_breaks_[j] > start_offset)
+          return line_breaks_[j];
+      }
+      return text_size;
+    } else {
+      for (int j = static_cast<int>(line_breaks_.size()) - 1; j >= 0; j--) {
+        if (line_breaks_[j] <= start_offset)
+          return line_breaks_[j];
+      }
+      return 0;
+    }
+  }
+
+  LONG result = start_offset;
+  for (;;) {
+    LONG pos;
+    if (direction == 1) {
+      if (result >= text_size)
+        return text_size;
+      pos = result;
+    } else {
+      if (result <= 0)
+        return 0;
+      pos = result - 1;
+    }
+
+    switch (boundary) {
+      case IA2_TEXT_BOUNDARY_CHAR:
+      case IA2_TEXT_BOUNDARY_LINE:
+        NOTREACHED();  // These are handled above.
+        break;
+      case IA2_TEXT_BOUNDARY_WORD:
+        if (IsWhitespace(text[pos]))
+          return result;
+        break;
+      case IA2_TEXT_BOUNDARY_PARAGRAPH:
+        if (text[pos] == '\n')
+          return result;
+      case IA2_TEXT_BOUNDARY_SENTENCE:
+        // Note that we don't actually have to implement sentence support;
+        // currently IAccessibleText functions return S_FALSE so that
+        // screenreaders will handle it on their own.
+        if ((text[pos] == '.' || text[pos] == '!' || text[pos] == '?') &&
+            (pos == text_size - 1 || IsWhitespace(text[pos + 1]))) {
+          return result;
+        }
+      case IA2_TEXT_BOUNDARY_ALL:
+      default:
+        break;
+    }
+
+    if (direction > 0) {
+      result++;
+    } else if (direction < 0) {
+      result--;
+    } else {
+      NOTREACHED();
+      return result;
+    }
+  }
+}
+
+void BrowserAccessibilityWin::InitRoleAndState() {
+  ia_state_ = 0;
+  ia2_state_ = IA2_STATE_OPAQUE;
+
+  if ((state_ >> WebAccessibility::STATE_CHECKED) & 1)
+    ia_state_ |= STATE_SYSTEM_CHECKED;
+  if ((state_ >> WebAccessibility::STATE_COLLAPSED) & 1)
+    ia_state_|= STATE_SYSTEM_COLLAPSED;
+  if ((state_ >> WebAccessibility::STATE_EXPANDED) & 1)
+    ia_state_|= STATE_SYSTEM_EXPANDED;
+  if ((state_ >> WebAccessibility::STATE_FOCUSABLE) & 1)
+    ia_state_|= STATE_SYSTEM_FOCUSABLE;
+  if ((state_ >> WebAccessibility::STATE_HASPOPUP) & 1)
+    ia_state_|= STATE_SYSTEM_HASPOPUP;
+  if ((state_ >> WebAccessibility::STATE_HOTTRACKED) & 1)
+    ia_state_|= STATE_SYSTEM_HOTTRACKED;
+  if ((state_ >> WebAccessibility::STATE_INDETERMINATE) & 1)
+    ia_state_|= STATE_SYSTEM_INDETERMINATE;
+  if ((state_ >> WebAccessibility::STATE_INVISIBLE) & 1)
+    ia_state_|= STATE_SYSTEM_INVISIBLE;
+  if ((state_ >> WebAccessibility::STATE_LINKED) & 1)
+    ia_state_|= STATE_SYSTEM_LINKED;
+  if ((state_ >> WebAccessibility::STATE_MULTISELECTABLE) & 1)
+    ia_state_|= STATE_SYSTEM_MULTISELECTABLE;
+  // TODO(ctguil): Support STATE_SYSTEM_EXTSELECTABLE/accSelect.
+  if ((state_ >> WebAccessibility::STATE_OFFSCREEN) & 1)
+    ia_state_|= STATE_SYSTEM_OFFSCREEN;
+  if ((state_ >> WebAccessibility::STATE_PRESSED) & 1)
+    ia_state_|= STATE_SYSTEM_PRESSED;
+  if ((state_ >> WebAccessibility::STATE_PROTECTED) & 1)
+    ia_state_|= STATE_SYSTEM_PROTECTED;
+  if ((state_ >> WebAccessibility::STATE_SELECTABLE) & 1)
+    ia_state_|= STATE_SYSTEM_SELECTABLE;
+  if ((state_ >> WebAccessibility::STATE_SELECTED) & 1)
+    ia_state_|= STATE_SYSTEM_SELECTED;
+  if ((state_ >> WebAccessibility::STATE_READONLY) & 1)
+    ia_state_|= STATE_SYSTEM_READONLY;
+  if ((state_ >> WebAccessibility::STATE_TRAVERSED) & 1)
+    ia_state_|= STATE_SYSTEM_TRAVERSED;
+  if ((state_ >> WebAccessibility::STATE_BUSY) & 1)
+    ia_state_|= STATE_SYSTEM_BUSY;
+  if ((state_ >> WebAccessibility::STATE_UNAVAILABLE) & 1)
+    ia_state_|= STATE_SYSTEM_UNAVAILABLE;
+
+  string16 html_tag;
+  GetAttribute(WebAccessibility::ATTR_HTML_TAG, &html_tag);
+  ia_role_ = 0;
+  ia2_role_ = 0;
+  switch (role_) {
+    case WebAccessibility::ROLE_ALERT:
+    case WebAccessibility::ROLE_ALERT_DIALOG:
+      ia_role_ = ROLE_SYSTEM_ALERT;
+      break;
+    case WebAccessibility::ROLE_APPLICATION:
+      ia_role_ = ROLE_SYSTEM_APPLICATION;
+      break;
+    case WebAccessibility::ROLE_ARTICLE:
+      ia_role_ = ROLE_SYSTEM_GROUPING;
+      ia2_role_ = IA2_ROLE_SECTION;
+      break;
+    case WebAccessibility::ROLE_BUSY_INDICATOR:
+      ia_role_ = ROLE_SYSTEM_ANIMATION;
+      break;
+    case WebAccessibility::ROLE_BUTTON:
+      ia_role_ = ROLE_SYSTEM_PUSHBUTTON;
+      break;
+    case WebAccessibility::ROLE_CELL:
+      ia_role_ = ROLE_SYSTEM_CELL;
+      break;
+    case WebAccessibility::ROLE_CHECKBOX:
+      ia_role_ = ROLE_SYSTEM_CHECKBUTTON;
+      break;
+    case WebAccessibility::ROLE_COLOR_WELL:
+      ia_role_ = ROLE_SYSTEM_CLIENT;
+      ia2_role_ = IA2_ROLE_COLOR_CHOOSER;
+      break;
+    case WebAccessibility::ROLE_COLUMN:
+      ia_role_ = ROLE_SYSTEM_COLUMN;
+      break;
+    case WebAccessibility::ROLE_COLUMN_HEADER:
+      ia_role_ = ROLE_SYSTEM_COLUMNHEADER;
+      break;
+    case WebAccessibility::ROLE_COMBO_BOX:
+      ia_role_ = ROLE_SYSTEM_COMBOBOX;
+      break;
+    case WebAccessibility::ROLE_DEFINITION_LIST_DEFINITION:
+      role_name_ = html_tag;
+      ia2_role_ = IA2_ROLE_PARAGRAPH;
+      break;
+    case WebAccessibility::ROLE_DEFINITION_LIST_TERM:
+      ia_role_ = ROLE_SYSTEM_LISTITEM;
+      break;
+    case WebAccessibility::ROLE_DIALOG:
+      ia_role_ = ROLE_SYSTEM_DIALOG;
+      break;
+    case WebAccessibility::ROLE_DISCLOSURE_TRIANGLE:
+      ia_role_ = ROLE_SYSTEM_OUTLINEBUTTON;
+      break;
+    case WebAccessibility::ROLE_DOCUMENT:
+    case WebAccessibility::ROLE_WEB_AREA:
+      ia_role_ = ROLE_SYSTEM_DOCUMENT;
+      ia_state_|= STATE_SYSTEM_READONLY;
+      ia_state_|= STATE_SYSTEM_FOCUSABLE;
+      break;
+    case WebAccessibility::ROLE_EDITABLE_TEXT:
+      ia_role_ = ROLE_SYSTEM_TEXT;
+      ia2_state_ |= IA2_STATE_SINGLE_LINE;
+      ia2_state_ |= IA2_STATE_EDITABLE;
+      break;
+    case WebAccessibility::ROLE_GRID:
+      ia_role_ = ROLE_SYSTEM_TABLE;
+      break;
+    case WebAccessibility::ROLE_GROUP:
+      if (html_tag == L"li") {
+        ia_role_ = ROLE_SYSTEM_LISTITEM;
+      } else {
+        if (html_tag.empty())
+          role_name_ = L"div";
+        else
+          role_name_ = html_tag;
+        ia2_role_ = IA2_ROLE_SECTION;
+      }
+      break;
+    case WebAccessibility::ROLE_GROW_AREA:
+      ia_role_ = ROLE_SYSTEM_GRIP;
+      break;
+    case WebAccessibility::ROLE_HEADING:
+      role_name_ = html_tag;
+      ia2_role_ = IA2_ROLE_HEADING;
+      break;
+    case WebAccessibility::ROLE_IMAGE:
+      ia_role_ = ROLE_SYSTEM_GRAPHIC;
+      break;
+    case WebAccessibility::ROLE_IMAGE_MAP:
+      role_name_ = html_tag;
+      ia2_role_ = IA2_ROLE_IMAGE_MAP;
+      break;
+    case WebAccessibility::ROLE_IMAGE_MAP_LINK:
+      ia_role_ = ROLE_SYSTEM_LINK;
+      ia_state_|= STATE_SYSTEM_LINKED;
+      break;
+    case WebAccessibility::ROLE_LANDMARK_APPLICATION:
+    case WebAccessibility::ROLE_LANDMARK_BANNER:
+    case WebAccessibility::ROLE_LANDMARK_COMPLEMENTARY:
+    case WebAccessibility::ROLE_LANDMARK_CONTENTINFO:
+    case WebAccessibility::ROLE_LANDMARK_MAIN:
+    case WebAccessibility::ROLE_LANDMARK_NAVIGATION:
+    case WebAccessibility::ROLE_LANDMARK_SEARCH:
+      ia_role_ = ROLE_SYSTEM_GROUPING;
+      ia2_role_ = IA2_ROLE_SECTION;
+      break;
+    case WebAccessibility::ROLE_LINK:
+    case WebAccessibility::ROLE_WEBCORE_LINK:
+      ia_role_ = ROLE_SYSTEM_LINK;
+      ia_state_|= STATE_SYSTEM_LINKED;
+      break;
+    case WebAccessibility::ROLE_LIST:
+      ia_role_ = ROLE_SYSTEM_LIST;
+      break;
+    case WebAccessibility::ROLE_LISTBOX:
+      ia_role_ = ROLE_SYSTEM_LIST;
+      break;
+    case WebAccessibility::ROLE_LISTBOX_OPTION:
+    case WebAccessibility::ROLE_LIST_ITEM:
+    case WebAccessibility::ROLE_LIST_MARKER:
+      ia_role_ = ROLE_SYSTEM_LISTITEM;
+      break;
+    case WebAccessibility::ROLE_MATH:
+      ia_role_ = ROLE_SYSTEM_EQUATION;
+      break;
+    case WebAccessibility::ROLE_MENU:
+    case WebAccessibility::ROLE_MENU_BUTTON:
+      ia_role_ = ROLE_SYSTEM_MENUPOPUP;
+      break;
+    case WebAccessibility::ROLE_MENU_BAR:
+      ia_role_ = ROLE_SYSTEM_MENUBAR;
+      break;
+    case WebAccessibility::ROLE_MENU_ITEM:
+    case WebAccessibility::ROLE_MENU_LIST_OPTION:
+      ia_role_ = ROLE_SYSTEM_MENUITEM;
+      break;
+    case WebAccessibility::ROLE_MENU_LIST_POPUP:
+      ia_role_ = ROLE_SYSTEM_MENUPOPUP;
+      break;
+    case WebAccessibility::ROLE_NOTE:
+      ia_role_ = ROLE_SYSTEM_GROUPING;
+      ia2_role_ = IA2_ROLE_NOTE;
+      break;
+    case WebAccessibility::ROLE_OUTLINE:
+      ia_role_ = ROLE_SYSTEM_OUTLINE;
+      break;
+    case WebAccessibility::ROLE_POPUP_BUTTON:
+      ia_role_ = ROLE_SYSTEM_COMBOBOX;
+      break;
+    case WebAccessibility::ROLE_PROGRESS_INDICATOR:
+      ia_role_ = ROLE_SYSTEM_PROGRESSBAR;
+      break;
+    case WebAccessibility::ROLE_RADIO_BUTTON:
+      ia_role_ = ROLE_SYSTEM_RADIOBUTTON;
+      break;
+    case WebAccessibility::ROLE_RADIO_GROUP:
+      ia_role_ = ROLE_SYSTEM_GROUPING;
+      ia2_role_ = IA2_ROLE_SECTION;
+      break;
+    case WebAccessibility::ROLE_REGION:
+      ia_role_ = ROLE_SYSTEM_GROUPING;
+      ia2_role_ = IA2_ROLE_SECTION;
+      break;
+    case WebAccessibility::ROLE_ROW:
+      ia_role_ = ROLE_SYSTEM_ROW;
+      break;
+    case WebAccessibility::ROLE_ROW_HEADER:
+      ia_role_ = ROLE_SYSTEM_ROWHEADER;
+      break;
+    case WebAccessibility::ROLE_RULER:
+      ia_role_ = ROLE_SYSTEM_CLIENT;
+      ia2_role_ = IA2_ROLE_RULER;
+      break;
+    case WebAccessibility::ROLE_SCROLLAREA:
+      ia_role_ = ROLE_SYSTEM_CLIENT;
+      ia2_role_ = IA2_ROLE_SCROLL_PANE;
+      break;
+    case WebAccessibility::ROLE_SCROLLBAR:
+      ia_role_ = ROLE_SYSTEM_SCROLLBAR;
+      break;
+    case WebAccessibility::ROLE_SLIDER:
+      ia_role_ = ROLE_SYSTEM_SLIDER;
+      break;
+    case WebAccessibility::ROLE_SPLIT_GROUP:
+      ia_role_ = ROLE_SYSTEM_CLIENT;
+      ia2_role_ = IA2_ROLE_SPLIT_PANE;
+      break;
+    case WebAccessibility::ROLE_ANNOTATION:
+    case WebAccessibility::ROLE_STATIC_TEXT:
+      ia_role_ = ROLE_SYSTEM_TEXT;
+      break;
+    case WebAccessibility::ROLE_STATUS:
+      ia_role_ = ROLE_SYSTEM_STATUSBAR;
+      break;
+    case WebAccessibility::ROLE_SPLITTER:
+      ia_role_ = ROLE_SYSTEM_SEPARATOR;
+      break;
+    case WebAccessibility::ROLE_TAB:
+      ia_role_ = ROLE_SYSTEM_PAGETAB;
+      break;
+    case WebAccessibility::ROLE_TABLE:
+      ia_role_ = ROLE_SYSTEM_TABLE;
+      break;
+    case WebAccessibility::ROLE_TABLE_HEADER_CONTAINER:
+      ia_role_ = ROLE_SYSTEM_GROUPING;
+      ia2_role_ = IA2_ROLE_SECTION;
+      break;
+    case WebAccessibility::ROLE_TAB_GROUP:
+    case WebAccessibility::ROLE_TAB_LIST:
+    case WebAccessibility::ROLE_TAB_PANEL:
+      ia_role_ = ROLE_SYSTEM_PAGETABLIST;
+      break;
+    case WebAccessibility::ROLE_TEXTAREA:
+      ia_role_ = ROLE_SYSTEM_TEXT;
+      ia2_state_ |= IA2_STATE_MULTI_LINE;
+      ia2_state_ |= IA2_STATE_EDITABLE;
+      ia2_state_ |= IA2_STATE_SELECTABLE_TEXT;
+      break;
+    case WebAccessibility::ROLE_TEXT_FIELD:
+      ia_role_ = ROLE_SYSTEM_TEXT;
+      ia2_state_ |= IA2_STATE_SINGLE_LINE;
+      ia2_state_ |= IA2_STATE_EDITABLE;
+      ia2_state_ |= IA2_STATE_SELECTABLE_TEXT;
+      break;
+    case WebAccessibility::ROLE_TIMER:
+      ia_role_ = ROLE_SYSTEM_CLOCK;
+      break;
+    case WebAccessibility::ROLE_TOOLBAR:
+      ia_role_ = ROLE_SYSTEM_TOOLBAR;
+      break;
+    case WebAccessibility::ROLE_TOOLTIP:
+      ia_role_ = ROLE_SYSTEM_TOOLTIP;
+      break;
+    case WebAccessibility::ROLE_TREE:
+      ia_role_ = ROLE_SYSTEM_OUTLINE;
+      break;
+    case WebAccessibility::ROLE_TREE_GRID:
+      ia_role_ = ROLE_SYSTEM_OUTLINE;
+      break;
+    case WebAccessibility::ROLE_TREE_ITEM:
+      ia_role_ = ROLE_SYSTEM_OUTLINEITEM;
+      break;
+    case WebAccessibility::ROLE_WINDOW:
+      ia_role_ = ROLE_SYSTEM_WINDOW;
+      break;
+
+    // TODO(dmazzoni): figure out the proper MSAA role for all of these.
+    case WebAccessibility::ROLE_BROWSER:
+    case WebAccessibility::ROLE_DIRECTORY:
+    case WebAccessibility::ROLE_DRAWER:
+    case WebAccessibility::ROLE_HELP_TAG:
+    case WebAccessibility::ROLE_IGNORED:
+    case WebAccessibility::ROLE_INCREMENTOR:
+    case WebAccessibility::ROLE_LOG:
+    case WebAccessibility::ROLE_MARQUEE:
+    case WebAccessibility::ROLE_MATTE:
+    case WebAccessibility::ROLE_RULER_MARKER:
+    case WebAccessibility::ROLE_SHEET:
+    case WebAccessibility::ROLE_SLIDER_THUMB:
+    case WebAccessibility::ROLE_SYSTEM_WIDE:
+    case WebAccessibility::ROLE_VALUE_INDICATOR:
+    default:
+      ia_role_ = ROLE_SYSTEM_CLIENT;
+      break;
+  }
+
+  // The role should always be set.
+  DCHECK(!role_name_.empty() || ia_role_);
+
+  // If we didn't explicitly set the IAccessible2 role, make it the same
+  // as the MSAA role.
+  if (!ia2_role_)
+    ia2_role_ = ia_role_;
+}
diff --git a/content/browser/accessibility/browser_accessibility_win.h b/content/browser/accessibility/browser_accessibility_win.h
new file mode 100644
index 0000000..fb8e014
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_win.h
@@ -0,0 +1,499 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_WIN_H_
+#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_WIN_H_
+#pragma once
+
+#include <atlbase.h>
+#include <atlcom.h>
+#include <oleacc.h>
+
+#include <vector>
+
+#include "content/browser/accessibility/browser_accessibility.h"
+#include "ia2_api_all.h"  // Generated
+#include "ISimpleDOMDocument.h"  // Generated
+#include "ISimpleDOMNode.h"  // Generated
+#include "ISimpleDOMText.h"  // Generated
+#include "webkit/glue/webaccessibility.h"
+
+class BrowserAccessibilityManagerWin;
+
+using webkit_glue::WebAccessibility;
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// BrowserAccessibilityWin
+//
+// Class implementing the windows accessible interface for the Browser-Renderer
+// communication of accessibility information, providing accessibility
+// to be used by screen readers and other assistive technology (AT).
+//
+////////////////////////////////////////////////////////////////////////////////
+class BrowserAccessibilityWin
+    : public BrowserAccessibility,
+      public CComObjectRootEx<CComMultiThreadModel>,
+      public IDispatchImpl<IAccessible2, &IID_IAccessible2,
+                           &LIBID_IAccessible2Lib>,
+      public IAccessibleImage,
+      public IAccessibleText,
+      public IServiceProvider,
+      public ISimpleDOMDocument,
+      public ISimpleDOMNode,
+      public ISimpleDOMText {
+ public:
+  BEGIN_COM_MAP(BrowserAccessibilityWin)
+    COM_INTERFACE_ENTRY2(IDispatch, IAccessible2)
+    COM_INTERFACE_ENTRY2(IAccessible, IAccessible2)
+    COM_INTERFACE_ENTRY(IAccessible2)
+    COM_INTERFACE_ENTRY(IAccessibleImage)
+    COM_INTERFACE_ENTRY(IAccessibleText)
+    COM_INTERFACE_ENTRY(IServiceProvider)
+    COM_INTERFACE_ENTRY(ISimpleDOMDocument)
+    COM_INTERFACE_ENTRY(ISimpleDOMNode)
+    COM_INTERFACE_ENTRY(ISimpleDOMText)
+  END_COM_MAP()
+
+  BrowserAccessibilityWin();
+
+  virtual ~BrowserAccessibilityWin();
+
+  //
+  // BrowserAccessibility methods.
+  //
+  virtual void Initialize();
+  virtual void NativeAddReference();
+  virtual void NativeReleaseReference();
+
+  //
+  // IAccessible methods.
+  //
+
+  // Performs the default action on a given object.
+  STDMETHODIMP accDoDefaultAction(VARIANT var_id);
+
+  // Retrieves the child element or child object at a given point on the screen.
+  STDMETHODIMP accHitTest(LONG x_left, LONG y_top, VARIANT* child);
+
+  // Retrieves the specified object's current screen location.
+  STDMETHODIMP accLocation(LONG* x_left,
+                           LONG* y_top,
+                           LONG* width,
+                           LONG* height,
+                           VARIANT var_id);
+
+  // Traverses to another UI element and retrieves the object.
+  STDMETHODIMP accNavigate(LONG nav_dir, VARIANT start, VARIANT* end);
+
+  // Retrieves an IDispatch interface pointer for the specified child.
+  STDMETHODIMP get_accChild(VARIANT var_child, IDispatch** disp_child);
+
+  // Retrieves the number of accessible children.
+  STDMETHODIMP get_accChildCount(LONG* child_count);
+
+  // Retrieves a string that describes the object's default action.
+  STDMETHODIMP get_accDefaultAction(VARIANT var_id, BSTR* default_action);
+
+  // Retrieves the object's description.
+  STDMETHODIMP get_accDescription(VARIANT var_id, BSTR* desc);
+
+  // Retrieves the object that has the keyboard focus.
+  STDMETHODIMP get_accFocus(VARIANT* focus_child);
+
+  // Retrieves the help information associated with the object.
+  STDMETHODIMP get_accHelp(VARIANT var_id, BSTR* help);
+
+  // Retrieves the specified object's shortcut.
+  STDMETHODIMP get_accKeyboardShortcut(VARIANT var_id, BSTR* access_key);
+
+  // Retrieves the name of the specified object.
+  STDMETHODIMP get_accName(VARIANT var_id, BSTR* name);
+
+  // Retrieves the IDispatch interface of the object's parent.
+  STDMETHODIMP get_accParent(IDispatch** disp_parent);
+
+  // Retrieves information describing the role of the specified object.
+  STDMETHODIMP get_accRole(VARIANT var_id, VARIANT* role);
+
+  // Retrieves the current state of the specified object.
+  STDMETHODIMP get_accState(VARIANT var_id, VARIANT* state);
+
+  // Returns the value associated with the object.
+  STDMETHODIMP get_accValue(VARIANT var_id, BSTR* value);
+
+  // Make an object take focus or extend the selection.
+  STDMETHODIMP accSelect(LONG flags_sel, VARIANT var_id);
+
+  STDMETHODIMP get_accHelpTopic(BSTR* help_file,
+                                VARIANT var_id,
+                                LONG* topic_id);
+
+  STDMETHODIMP get_accSelection(VARIANT* selected);
+
+  // Deprecated methods, not implemented.
+  STDMETHODIMP put_accName(VARIANT var_id, BSTR put_name) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP put_accValue(VARIANT var_id, BSTR put_val) {
+    return E_NOTIMPL;
+  }
+
+  //
+  // IAccessible2 methods.
+  //
+
+  // Returns role from a longer list of possible roles.
+  STDMETHODIMP role(LONG* role);
+
+  // Returns the state bitmask from a larger set of possible states.
+  STDMETHODIMP get_states(AccessibleStates* states);
+
+  // Returns the attributes specific to this IAccessible2 object,
+  // such as a cell's formula.
+  STDMETHODIMP get_attributes(BSTR* attributes);
+
+  // Get the unique ID of this object so that the client knows if it's
+  // been encountered previously.
+  STDMETHODIMP get_uniqueID(LONG* unique_id);
+
+  // Get the window handle of the enclosing window.
+  STDMETHODIMP get_windowHandle(HWND* window_handle);
+
+  // Get this object's index in its parent object.
+  STDMETHODIMP get_indexInParent(LONG* index_in_parent);
+
+  // IAccessible2 methods not implemented.
+  STDMETHODIMP get_extendedRole(BSTR* extended_role) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_nRelations(LONG* n_relations) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_relation(LONG relation_index,
+                            IAccessibleRelation** relation) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_relations(LONG max_relations,
+                             IAccessibleRelation** relations,
+                             LONG* n_relations) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP scrollTo(enum IA2ScrollType scroll_type) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP scrollToPoint(enum IA2CoordinateType coordinate_type,
+                             LONG x,
+                             LONG y) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_groupPosition(LONG* group_level,
+                                 LONG* similar_items_in_group,
+                                 LONG* position_in_group) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_localizedExtendedRole(BSTR* localized_extended_role) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_nExtendedStates(LONG* n_extended_states) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_extendedStates(LONG max_extended_states,
+                                  BSTR** extended_states,
+                                  LONG* n_extended_states) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_localizedExtendedStates(LONG max_localized_extended_states,
+                                           BSTR** localized_extended_states,
+                                           LONG* n_localized_extended_states) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_locale(IA2Locale* locale) {
+    return E_NOTIMPL;
+  }
+
+  //
+  // IAccessibleImage methods.
+  //
+
+  STDMETHODIMP get_description(BSTR* description);
+
+  STDMETHODIMP get_imagePosition(enum IA2CoordinateType coordinate_type,
+                                 LONG* x, LONG* y);
+
+  STDMETHODIMP get_imageSize(LONG* height, LONG* width);
+
+  //
+  // IAccessibleText methods.
+  //
+
+  STDMETHODIMP get_nCharacters(LONG* n_characters);
+
+  STDMETHODIMP get_caretOffset(LONG* offset);
+
+  STDMETHODIMP get_nSelections(LONG* n_selections);
+
+  STDMETHODIMP get_selection(LONG selection_index,
+                             LONG* start_offset,
+                             LONG* end_offset);
+
+  STDMETHODIMP get_text(LONG start_offset, LONG end_offset, BSTR* text);
+
+  STDMETHODIMP get_textAtOffset(LONG offset,
+                                enum IA2TextBoundaryType boundary_type,
+                                LONG* start_offset, LONG* end_offset,
+                                BSTR* text);
+
+  STDMETHODIMP get_textBeforeOffset(LONG offset,
+                                    enum IA2TextBoundaryType boundary_type,
+                                    LONG* start_offset, LONG* end_offset,
+                                    BSTR* text);
+
+  STDMETHODIMP get_textAfterOffset(LONG offset,
+                                   enum IA2TextBoundaryType boundary_type,
+                                   LONG* start_offset, LONG* end_offset,
+                                   BSTR* text);
+
+  // IAccessibleText methods not implemented.
+  STDMETHODIMP addSelection(LONG start_offset, LONG end_offset) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_attributes(LONG offset, LONG* start_offset, LONG* end_offset,
+                              BSTR* text_attributes) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_characterExtents(LONG offset,
+                                    enum IA2CoordinateType coord_type,
+                                    LONG* x, LONG* y,
+                                    LONG* width, LONG* height) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_offsetAtPoint(LONG x, LONG y,
+                                 enum IA2CoordinateType coord_type,
+                                 LONG* offset) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP removeSelection(LONG selection_index) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP setCaretOffset(LONG offset) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP setSelection(LONG selection_index,
+                            LONG start_offset,
+                            LONG end_offset) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP scrollSubstringTo(LONG start_index,
+                                 LONG end_index,
+                                 enum IA2ScrollType scroll_type) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP scrollSubstringToPoint(LONG start_index, LONG end_index,
+                                      enum IA2CoordinateType coordinate_type,
+                                      LONG x, LONG y) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_newText(IA2TextSegment* new_text) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP get_oldText(IA2TextSegment* old_text) {
+    return E_NOTIMPL;
+  }
+
+  //
+  // ISimpleDOMDocument methods.
+  //
+
+  STDMETHODIMP get_URL(BSTR* url);
+
+  STDMETHODIMP get_title(BSTR* title);
+
+  STDMETHODIMP get_mimeType(BSTR* mime_type);
+
+  STDMETHODIMP get_docType(BSTR* doc_type);
+
+  STDMETHODIMP get_nameSpaceURIForID(
+      short name_space_id, BSTR *name_space_uri) {
+    return E_NOTIMPL;
+  }
+  STDMETHODIMP put_alternateViewMediaTypes(
+      BSTR *comma_separated_media_types) {
+    return E_NOTIMPL;
+  }
+
+  //
+  // ISimpleDOMNode methods.
+  //
+
+  STDMETHODIMP get_nodeInfo(
+      BSTR* node_name,
+      short* name_space_id,
+      BSTR* node_value,
+      unsigned int* num_children,
+      unsigned int* unique_id,
+      unsigned short* node_type);
+
+  STDMETHODIMP get_attributes(
+      unsigned short max_attribs,
+      BSTR* attrib_names,
+      short* name_space_id,
+      BSTR* attrib_values,
+      unsigned short* num_attribs);
+
+  STDMETHODIMP get_attributesForNames(
+      unsigned short num_attribs,
+      BSTR* attrib_names,
+      short* name_space_id,
+      BSTR* attrib_values);
+
+  STDMETHODIMP get_computedStyle(
+      unsigned short max_style_properties,
+      boolean use_alternate_view,
+      BSTR *style_properties,
+      BSTR *style_values,
+      unsigned short *num_style_properties);
+
+  STDMETHODIMP get_computedStyleForProperties(
+      unsigned short num_style_properties,
+      boolean use_alternate_view,
+      BSTR* style_properties,
+      BSTR* style_values);
+
+  STDMETHODIMP scrollTo(boolean placeTopLeft);
+
+  STDMETHODIMP get_parentNode(ISimpleDOMNode** node);
+
+  STDMETHODIMP get_firstChild(ISimpleDOMNode** node);
+
+  STDMETHODIMP get_lastChild(ISimpleDOMNode** node);
+
+  STDMETHODIMP get_previousSibling(ISimpleDOMNode** node);
+
+  STDMETHODIMP get_nextSibling(ISimpleDOMNode** node);
+
+  STDMETHODIMP get_childAt(
+      unsigned int child_index,
+      ISimpleDOMNode** node);
+
+  STDMETHODIMP get_innerHTML(BSTR* innerHTML) {
+    return E_NOTIMPL;
+  }
+
+  STDMETHODIMP get_localInterface(void** local_interface) {
+    return E_NOTIMPL;
+  }
+
+  STDMETHODIMP get_language(BSTR* language) {
+    return E_NOTIMPL;
+  }
+
+  //
+  // ISimpleDOMText methods.
+  //
+
+  STDMETHODIMP get_domText(BSTR* dom_text);
+
+  STDMETHODIMP get_clippedSubstringBounds(
+      unsigned int start_index,
+      unsigned int end_index,
+      int* x,
+      int* y,
+      int* width,
+      int* height) {
+    return E_NOTIMPL;
+  }
+
+  STDMETHODIMP get_unclippedSubstringBounds(
+      unsigned int start_index,
+      unsigned int end_index,
+      int* x,
+      int* y,
+      int* width,
+      int* height) {
+    return E_NOTIMPL;
+  }
+
+  STDMETHODIMP scrollToSubstring(
+      unsigned int start_index,
+      unsigned int end_index)  {
+    return E_NOTIMPL;
+  }
+
+  STDMETHODIMP get_fontFamily(BSTR *font_family)  {
+    return E_NOTIMPL;
+  }
+
+  //
+  // IServiceProvider methods.
+  //
+
+  STDMETHODIMP QueryService(REFGUID guidService, REFIID riid, void** object);
+
+  //
+  // CComObjectRootEx methods.
+  //
+
+  HRESULT WINAPI InternalQueryInterface(void* this_ptr,
+                                        const _ATL_INTMAP_ENTRY* entries,
+                                        REFIID iid,
+                                        void** object);
+
+ private:
+  // Add one to the reference count and return the same object. Always
+  // use this method when returning a BrowserAccessibilityWin object as
+  // an output parameter to a COM interface, never use it otherwise.
+  BrowserAccessibilityWin* NewReference();
+
+  // Many MSAA methods take a var_id parameter indicating that the operation
+  // should be performed on a particular child ID, rather than this object.
+  // This method tries to figure out the target object from |var_id| and
+  // returns a pointer to the target object if it exists, otherwise NULL.
+  // Does not return a new reference.
+  BrowserAccessibilityWin* GetTargetFromChildID(const VARIANT& var_id);
+
+  // Initialize the role and state metadata from the role enum and state
+  // bitmasks defined in webkit/glue/webaccessibility.h.
+  void InitRoleAndState();
+
+  // Retrieve the string value of an attribute from the attribute map and
+  // if found and nonempty, allocate a new BSTR (with SysAllocString)
+  // and return S_OK. If not found or empty, return S_FALSE.
+  HRESULT GetAttributeAsBstr(
+      WebAccessibility::Attribute attribute, BSTR* value_bstr);
+
+  // Escape a string like it would be escaped for a URL or HTML form.
+  string16 Escape(const string16& str);
+
+  // Get the text of this node for the purposes of IAccessibleText - it may
+  // be the name, it may be the value, etc. depending on the role.
+  const string16& TextForIAccessibleText();
+
+  // If offset is a member of IA2TextSpecialOffsets this function updates the
+  // value of offset and returns, otherwise offset remains unchanged.
+  void HandleSpecialTextOffset(const string16& text, LONG* offset);
+
+  // Search forwards (direction == 1) or backwards (direction == -1) from
+  // the given offset until the given IAccessible2 boundary (like word,
+  // sentence) is found, and return its offset.
+  LONG FindBoundary(const string16& text,
+                    IA2TextBoundaryType boundary,
+                    LONG start_offset,
+                    LONG direction);
+
+  // IAccessible role and state.
+  int32 ia_role_;
+  int32 ia_state_;
+
+  // IAccessible2 role and state.
+  int32 ia2_role_;
+  int32 ia2_state_;
+
+  // Give BrowserAccessibility::Create access to our constructor.
+  friend class BrowserAccessibility;
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityWin);
+};
+
+#endif  // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_WIN_H_
diff --git a/content/browser/renderer_host/render_widget_host.cc b/content/browser/renderer_host/render_widget_host.cc
index 1f98484..b962f6e 100644
--- a/content/browser/renderer_host/render_widget_host.cc
+++ b/content/browser/renderer_host/render_widget_host.cc
@@ -11,6 +11,7 @@
 #include "base/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/utf_string_conversions.h"
+#include "content/browser/accessibility/browser_accessibility_state.h"
 #include "content/browser/gpu/gpu_process_host.h"
 #include "content/browser/renderer_host/backing_store.h"
 #include "content/browser/renderer_host/backing_store_manager.h"
@@ -90,7 +91,8 @@ RenderWidgetHost::RenderWidgetHost(RenderProcessHost* process,
   process_->WidgetRestored();
 
   if (CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kForceRendererAccessibility)) {
+          switches::kForceRendererAccessibility) ||
+      BrowserAccessibilityState::GetInstance()->IsAccessibleBrowser()) {
     EnableRendererAccessibility();
   }
 }
diff --git a/content/content_browser.gypi b/content/content_browser.gypi
index e41827f..ec460e2 100644
--- a/content/content_browser.gypi
+++ b/content/content_browser.gypi
@@ -20,11 +20,29 @@
         '../third_party/WebKit/Source/WebKit/chromium/WebKit.gyp:webkit',
         '../third_party/zlib/zlib.gyp:zlib',
         '../ui/ui.gyp:ui_base',
+        '../webkit/support/webkit_support.gyp:webkit_resources',
       ],
       'include_dirs': [
         '..',
       ],
       'sources': [
+        'browser/accessibility/browser_accessibility.cc',
+        'browser/accessibility/browser_accessibility.h',
+        'browser/accessibility/browser_accessibility_cocoa.h',
+        'browser/accessibility/browser_accessibility_cocoa.mm',
+        'browser/accessibility/browser_accessibility_delegate_mac.h',
+        'browser/accessibility/browser_accessibility_mac.h',
+        'browser/accessibility/browser_accessibility_mac.mm',
+        'browser/accessibility/browser_accessibility_manager.cc',
+        'browser/accessibility/browser_accessibility_manager.h',
+        'browser/accessibility/browser_accessibility_manager_mac.h',
+        'browser/accessibility/browser_accessibility_manager_mac.mm',
+        'browser/accessibility/browser_accessibility_manager_win.cc',
+        'browser/accessibility/browser_accessibility_manager_win.h',
+        'browser/accessibility/browser_accessibility_state.cc',
+        'browser/accessibility/browser_accessibility_state.h',
+        'browser/accessibility/browser_accessibility_win.cc',
+        'browser/accessibility/browser_accessibility_win.h',
         'browser/appcache/appcache_dispatcher_host.cc',
         'browser/appcache/appcache_dispatcher_host.h',
         'browser/appcache/appcache_frontend_proxy.cc',
@@ -422,6 +440,12 @@
             'browser/renderer_host/p2p/socket_dispatcher_host.h',
           ],
         }],
+        ['OS=="win"', {
+          'dependencies': [
+            '../third_party/iaccessible2/iaccessible2.gyp:iaccessible2',
+            '../third_party/isimpledom/isimpledom.gyp:isimpledom',
+          ]
+        }],
         ['toolkit_uses_gtk == 1', {
           'dependencies': [
             '../build/linux/system.gyp:dbus-glib',