Adds propagation and handling of render-side focus events, for the benefit of assistive technologies (accessibility). Also cleans up the handling of WM_GETOBJECT in RenderWidgetHostViewWin and WidgetWin, as well as in BrowserAccessibilityManager.

Review URL: http://codereview.chromium.org/115374

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@16449 0039d316-1c4b-4281-b951-d872f2087c98

10 files changed, 136 insertions, 44 deletions

diff --git a/webkit/glue/chrome_client_impl.cc b/webkit/glue/chrome_client_impl.cc
index b235d35..9553e93 100644
--- a/webkit/glue/chrome_client_impl.cc
+++ b/webkit/glue/chrome_client_impl.cc
@@ -7,8 +7,11 @@
 #include "base/compiler_specific.h"
 
 MSVC_PUSH_WARNING_LEVEL(0);
+#include "AccessibilityObject.h"
+#include "AXObjectCache.h"
 #include "Console.h"
 #include "Cursor.h"
+#include "Document.h"
 #include "DocumentLoader.h"
 #include "FloatRect.h"
 #include "FileChooser.h"
@@ -16,6 +19,7 @@ MSVC_PUSH_WARNING_LEVEL(0);
 #include "FrameView.h"
 #include "HitTestResult.h"
 #include "IntRect.h"
+#include "Node.h"
 #include "Page.h"
 #include "PopupMenuChromium.h"
 #include "ScriptController.h"
@@ -29,7 +33,6 @@ MSVC_POP_WARNING();
 
 #include "webkit/glue/chrome_client_impl.h"
 
-#include "base/logging.h"
 #include "base/gfx/rect.h"
 #include "googleurl/src/gurl.h"
 #include "webkit/api/public/WebInputEvent.h"
@@ -141,6 +144,28 @@ void ChromeClientImpl::focus() {
   WebViewDelegate* delegate = webview_->delegate();
   if (delegate)
     delegate->Focus(webview_);
+
+  // If accessibility is enabled, we should notify assistive technology that the
+  // active AccessibilityObject changed.
+  WebCore::Document* doc = webview_->GetFocusedWebCoreFrame()->document();
+
+  if (doc && doc->axObjectCache()->accessibilityEnabled()) {
+    WebCore::Node* focused_node = webview_->GetFocusedNode();
+
+    if (!focused_node) {
+      // Could not retrieve focused Node.
+      return;
+    }
+
+    // Retrieve the focused AccessibilityObject.
+    WebCore::AccessibilityObject* focused_acc_obj =
+        doc->axObjectCache()->getOrCreate(focused_node->renderer());
+
+    // Alert assistive technology that focus changed.
+    if (focused_acc_obj) {
+      delegate->FocusAccessibilityObject(focused_acc_obj);
+    }
+  }
 }
 
 void ChromeClientImpl::unfocus() {
@@ -201,7 +226,8 @@ static inline bool CurrentEventShouldCauseBackgroundTab(
   if (input_event->type != WebInputEvent::MouseUp)
     return false;
 
-  const WebMouseEvent* mouse_event = static_cast<const WebMouseEvent*>(input_event);
+  const WebMouseEvent* mouse_event =
+      static_cast<const WebMouseEvent*>(input_event);
   return (mouse_event->button == WebMouseEvent::ButtonMiddle);
 }
 
@@ -294,7 +320,8 @@ void ChromeClientImpl::addMessageToConsole(WebCore::MessageSource source,
   }
   WebDevToolsAgentImpl* devtools_agent = webview_->GetWebDevToolsAgentImpl();
   if (devtools_agent) {
-    devtools_agent->AddMessageToConsole(source, level, message, line_no, source_id);
+    devtools_agent->AddMessageToConsole(source, level, message, line_no,
+                                        source_id);
   }
 }
 
diff --git a/webkit/glue/chrome_client_impl.h b/webkit/glue/chrome_client_impl.h
index e372f7c..3a3fdc5 100644
--- a/webkit/glue/chrome_client_impl.h
+++ b/webkit/glue/chrome_client_impl.h
@@ -24,7 +24,7 @@ struct WindowFeatures;
 // Handles window-level notifications from WebCore on behalf of a WebView.
 class ChromeClientImpl : public WebCore::ChromeClientChromium {
  public:
-  ChromeClientImpl(WebViewImpl* webview);
+  explicit ChromeClientImpl(WebViewImpl* webview);
   virtual ~ChromeClientImpl();
 
   WebViewImpl* webview() const { return webview_; }
@@ -67,7 +67,8 @@ class ChromeClientImpl : public WebCore::ChromeClientChromium {
   virtual void setResizable(bool);
 
   virtual void addMessageToConsole(WebCore::MessageSource source,
-                                   WebCore::MessageLevel level, const WebCore::String& message,
+                                   WebCore::MessageLevel level,
+                                   const WebCore::String& message,
                                    unsigned int lineNumber,
                                    const WebCore::String& sourceID);
 
diff --git a/webkit/glue/glue_accessibility_object.cc b/webkit/glue/glue_accessibility_object.cc
index 17a693e..8c056eb 100644
--- a/webkit/glue/glue_accessibility_object.cc
+++ b/webkit/glue/glue_accessibility_object.cc
@@ -134,7 +134,7 @@ GlueAccessibilityObject* GlueAccessibilityObject::Navigate(
 GlueAccessibilityObject* GlueAccessibilityObject::GetChild(int child_id) {
   AccessibilityObject* child_obj;
   if (!GetAccessibilityObjectForChild(child_id, child_obj))
-    return false;
+    return NULL;
 
   // TODO(klink): simple object child?
   ToWrapper(child_obj)->ref();
diff --git a/webkit/glue/glue_accessibility_object.h b/webkit/glue/glue_accessibility_object.h
index 137a7e3..f94f9a1 100644
--- a/webkit/glue/glue_accessibility_object.h
+++ b/webkit/glue/glue_accessibility_object.h
@@ -27,6 +27,8 @@ class GlueAccessibilityObject : public WebCore::AccessibilityObjectWrapper {
  public:
   static GlueAccessibilityObject* CreateInstance(WebCore::AccessibilityObject*);
 
+  virtual ~GlueAccessibilityObject() {}
+
   // Performs the default action on a given object.
   bool DoDefaultAction(int child_id);
 
@@ -91,7 +93,6 @@ class GlueAccessibilityObject : public WebCore::AccessibilityObjectWrapper {
 
  protected:
   explicit GlueAccessibilityObject(WebCore::AccessibilityObject*);
-  virtual ~GlueAccessibilityObject() {}
 
   // Helper functions.
   WebCore::String name() const;
diff --git a/webkit/glue/webaccessibility.h b/webkit/glue/webaccessibility.h
index 538e612..250c665 100644
--- a/webkit/glue/webaccessibility.h
+++ b/webkit/glue/webaccessibility.h
@@ -117,6 +117,10 @@ class WebAccessibility {
     // Id of accessible child, whose information is being requested.
     int child_id;
 
+    // Indicates if the |child_id| refers to a direct child of the active
+    // accessibility object (true) or not (false).
+    bool direct_descendant;
+
     // LONG input parameters, used differently depending on the function called.
     long input_long1;
     long input_long2;
diff --git a/webkit/glue/webaccessibilitymanager.h b/webkit/glue/webaccessibilitymanager.h
index cebe94c..c94fbb9 100644
--- a/webkit/glue/webaccessibilitymanager.h
+++ b/webkit/glue/webaccessibilitymanager.h
@@ -7,6 +7,10 @@
 
 #include "webkit/glue/webaccessibility.h"
 
+namespace WebCore {
+class AccessibilityObject;
+}
+
 class WebView;
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -24,6 +28,7 @@ class WebAccessibilityManager {
   WebAccessibilityManager() {}
   virtual ~WebAccessibilityManager() {}
 
+  // Creates a new instance of WebAccessibilityManager.
   static WebAccessibilityManager* Create();
 
   // Retrieves the accessibility information as requested in in_params, by
@@ -39,13 +44,17 @@ class WebAccessibilityManager {
   // false otherwise.
   virtual bool ClearAccObjMap(int acc_obj_id, bool clear_all) = 0;
 
+  // Retrieves the id of the input AccessibilityObject, due to a focus event.
+  // Returns an id greater than or equal to 0 if successful, -1 otherwise.
+  virtual int FocusAccObj(WebCore::AccessibilityObject* acc_obj) = 0;
+
+ private:
   // Retrieves the RenderObject associated with this WebView, and uses it to
   // initialize the root of the GlueAccessibilityObject tree with the
   // associated accessibility information. Returns true if successful, false
   // otherwise.
   virtual bool InitAccObjRoot(WebView* view) = 0;
 
- private:
   DISALLOW_COPY_AND_ASSIGN(WebAccessibilityManager);
 };
 
diff --git a/webkit/glue/webaccessibilitymanager_impl.cc b/webkit/glue/webaccessibilitymanager_impl.cc
index 57ac0c7..f765127 100644
--- a/webkit/glue/webaccessibilitymanager_impl.cc
+++ b/webkit/glue/webaccessibilitymanager_impl.cc
@@ -34,7 +34,13 @@ WebAccessibilityManager* WebAccessibilityManager::Create() {
 
 // class WebAccessibilityManagerImpl
 WebAccessibilityManagerImpl::WebAccessibilityManagerImpl()
-    : root_(new GlueAccessibilityObjectRoot) {
+    : root_(new GlueAccessibilityObjectRoot),
+      acc_obj_id_(0) {
+}
+
+WebAccessibilityManagerImpl::~WebAccessibilityManagerImpl() {
+  int_to_glue_acc_obj_map_.clear();
+  acc_obj_to_int_map_.clear();
 }
 
 bool WebAccessibilityManagerImpl::GetAccObjInfo(WebView* view,
@@ -45,18 +51,28 @@ bool WebAccessibilityManagerImpl::GetAccObjInfo(WebView* view,
     return false;
   }
 
-  // Find GlueAccessibilityObject requested by [in_params.object_id].
-  IntToAccObjMap::iterator it =
-      int_to_acc_obj_map_.find(in_params.object_id);
-  if (it == int_to_acc_obj_map_.end() || !it->second) {
+  // Function input parameters.
+  int object_id = in_params.object_id;
+  int child_id = in_params.child_id;
+
+  if (!in_params.direct_descendant) {
+    // Object is not a direct child, re-map the input parameters accordingly.
+    // The object to be retrieved is referred to by the |in_params.child_id|, as
+    // a result of e.g. a focus event. The local |child_id| is set to 0, to
+    // indicate that any function call should refer to the object itself.
+    object_id = in_params.child_id;
+    child_id = 0;
+  }
+
+  // Find GlueAccessibilityObject requested by |object_id|.
+  IntToGlueAccObjMap::iterator it =
+      int_to_glue_acc_obj_map_.find(object_id);
+  if (it == int_to_glue_acc_obj_map_.end() || !it->second) {
     // Map did not contain a valid instance of the data requested.
     return false;
   }
   RefPtr<GlueAccessibilityObject> active_acc_obj = it->second;
 
-  // Function input parameters.
-  int child_id = in_params.child_id;
-
   // Temp paramters for holding output information.
   RefPtr<GlueAccessibilityObject> out_acc_obj = NULL;
   WebCore::String out_string;
@@ -156,7 +172,8 @@ bool WebAccessibilityManagerImpl::GetAccObjInfo(WebView* view,
     out_params->output_string = StringToString16(out_string);
 
   if (out_acc_obj) {
-    AccObjToIntMap::iterator it = acc_obj_to_int_map_.find(out_acc_obj.get());
+    AccObjToIntMap::iterator it =
+        acc_obj_to_int_map_.find(out_acc_obj->accessibilityObject());
 
     if (it != acc_obj_to_int_map_.end()) {
       // Data already present in map, return previously assigned id.
@@ -164,8 +181,8 @@ bool WebAccessibilityManagerImpl::GetAccObjInfo(WebView* view,
       out_params->output_long1 = -1;
     } else {
       // Insert new GlueAccessibilityObject in hashmaps.
-      int_to_acc_obj_map_[acc_obj_id_] = out_acc_obj.get();
-      acc_obj_to_int_map_[out_acc_obj.get()] = acc_obj_id_;
+      int_to_glue_acc_obj_map_[acc_obj_id_] = out_acc_obj.get();
+      acc_obj_to_int_map_[out_acc_obj->accessibilityObject()] = acc_obj_id_;
       out_params->object_id = acc_obj_id_++;
       out_params->output_long1 = -1;
     }
@@ -175,9 +192,6 @@ bool WebAccessibilityManagerImpl::GetAccObjInfo(WebView* view,
 }
 
 bool WebAccessibilityManagerImpl::InitAccObjRoot(WebView* view) {
-  // Root id is always 0.
-  acc_obj_id_ = 0;
-
   // Enable accessibility and retrieve Document.
   WebCore::AXObjectCache::enableAccessibility();
   WebFrameImpl* main_frame_impl =
@@ -199,8 +213,9 @@ bool WebAccessibilityManagerImpl::InitAccObjRoot(WebView* view) {
         axObjectCache()->getOrCreate(doc->renderer()));
   }
   // Insert root in hashmaps.
-  int_to_acc_obj_map_[acc_obj_id_] = root_->acc_obj_root_.get();
-  acc_obj_to_int_map_[root_->acc_obj_root_.get()] = acc_obj_id_++;
+  int_to_glue_acc_obj_map_[acc_obj_id_] = root_->acc_obj_root_.get();
+  acc_obj_to_int_map_[root_->acc_obj_root_->accessibilityObject()] =
+      acc_obj_id_++;
 
   return true;
 }
@@ -209,27 +224,28 @@ bool WebAccessibilityManagerImpl::ClearAccObjMap(int acc_obj_id,
                                                  bool clear_all) {
   if (clear_all) {
     // Clear maps and invalidate root.
-    int_to_acc_obj_map_.clear();
+    int_to_glue_acc_obj_map_.clear();
     acc_obj_to_int_map_.clear();
     root_->acc_obj_root_ = 0;
     return true;
   }
 
-  IntToAccObjMap::iterator it = int_to_acc_obj_map_.find(acc_obj_id);
+  IntToGlueAccObjMap::iterator it = int_to_glue_acc_obj_map_.find(acc_obj_id);
 
-  if (it == int_to_acc_obj_map_.end()) {
+  if (it == int_to_glue_acc_obj_map_.end()) {
     // Element not found.
     return false;
   }
 
   if (it->second) {
     // Erase element from reverse hashmap.
-    AccObjToIntMap::iterator it2 = acc_obj_to_int_map_.find(it->second);
+    AccObjToIntMap::iterator it2 =
+        acc_obj_to_int_map_.find(it->second->accessibilityObject());
 
     if (it2 != acc_obj_to_int_map_.end())
       acc_obj_to_int_map_.erase(it2);
   }
-  int_to_acc_obj_map_.erase(it);
+  int_to_glue_acc_obj_map_.erase(it);
 
   if (acc_obj_id == 0) {
     // Invalidate root.
@@ -238,4 +254,25 @@ bool WebAccessibilityManagerImpl::ClearAccObjMap(int acc_obj_id,
   return true;
 }
 
+int WebAccessibilityManagerImpl::FocusAccObj(
+    WebCore::AccessibilityObject* acc_obj) {
+  if (!acc_obj) {
+    // Return with failure.
+    return -1;
+  }
+
+  AccObjToIntMap::iterator it = acc_obj_to_int_map_.find(acc_obj);
+
+  if (it != acc_obj_to_int_map_.end())
+    return it->second;
+
+  // Insert new accessibility object in hashmaps and return its newly
+  // assigned accessibility object id.
+  int_to_glue_acc_obj_map_[acc_obj_id_] =
+      GlueAccessibilityObject::CreateInstance(acc_obj);
+  acc_obj_to_int_map_[acc_obj] = acc_obj_id_;
+
+  return acc_obj_id_++;
+}
+
 }  // namespace webkit_glue
diff --git a/webkit/glue/webaccessibilitymanager_impl.h b/webkit/glue/webaccessibilitymanager_impl.h
index fe28e4e..1bc0607 100644
--- a/webkit/glue/webaccessibilitymanager_impl.h
+++ b/webkit/glue/webaccessibilitymanager_impl.h
@@ -10,10 +10,6 @@
 
 class GlueAccessibilityObject;
 
-namespace webkit_glue {
-typedef base::hash_map<int, GlueAccessibilityObject*> IntToAccObjMap;
-typedef base::hash_map<GlueAccessibilityObject*, int> AccObjToIntMap;
-
 ////////////////////////////////////////////////////////////////////////////////
 //
 // WebAccessibilityManagerImpl
@@ -24,21 +20,23 @@ typedef base::hash_map<GlueAccessibilityObject*, int> AccObjToIntMap;
 // the requested information from the active AccessibilityObject, through the
 // GlueAccessibilityObject.
 ////////////////////////////////////////////////////////////////////////////////
+
+namespace webkit_glue {
+
 class WebAccessibilityManagerImpl : public WebAccessibilityManager {
  public:
   // From WebAccessibilityManager.
   bool GetAccObjInfo(WebView* view, const WebAccessibility::InParams& in_params,
                      WebAccessibility::OutParams* out_params);
-
-  // From WebAccessibilityManager.
   bool ClearAccObjMap(int acc_obj_id, bool clear_all);
+  int FocusAccObj(WebCore::AccessibilityObject* acc_obj);
 
  protected:
   // Needed so WebAccessibilityManager::Create can call our constructor.
   friend class WebAccessibilityManager;
 
   WebAccessibilityManagerImpl();
-  ~WebAccessibilityManagerImpl() {}
+  ~WebAccessibilityManagerImpl();
 
  private:
   // From WebAccessibilityManager.
@@ -49,17 +47,21 @@ class WebAccessibilityManagerImpl : public WebAccessibilityManager {
   struct GlueAccessibilityObjectRoot;
   GlueAccessibilityObjectRoot* root_;
 
+  typedef base::hash_map<int, GlueAccessibilityObject*> IntToGlueAccObjMap;
+  typedef base::hash_map<WebCore::AccessibilityObject*, int> AccObjToIntMap;
+
   // Hashmap for cashing of elements in use by the AT, mapping id (int) to a
   // GlueAccessibilityObject pointer.
-  IntToAccObjMap int_to_acc_obj_map_;
+  IntToGlueAccObjMap int_to_glue_acc_obj_map_;
   // Hashmap for cashing of elements in use by the AT, mapping a
-  // GlueAccessibilityObject pointer to its id (int). Needed for reverse lookup,
+  // AccessibilityObject pointer to its id (int). Needed for reverse lookup,
   // to ensure unnecessary duplicate entries are not created in the
-  // IntToAccObjMap (above).
+  // IntToGlueAccObjMap (above) and for focus changes in WebKit.
   AccObjToIntMap acc_obj_to_int_map_;
 
-  // Unique identifier for retrieving a GlueAccessibilityObject from the page's
-  // hashmaps.
+  // Unique identifier for retrieving an accessibility object from the page's
+  // hashmaps. Id is always 0 for the root of the accessibility object
+  // hierarchy (on a per-renderer process basis).
   int acc_obj_id_;
 
   DISALLOW_COPY_AND_ASSIGN(WebAccessibilityManagerImpl);
diff --git a/webkit/glue/webview_delegate.h b/webkit/glue/webview_delegate.h
index 525f745..7d503ad 100644
--- a/webkit/glue/webview_delegate.h
+++ b/webkit/glue/webview_delegate.h
@@ -37,6 +37,10 @@ namespace webkit_glue {
 class WebMediaPlayerDelegate;
 }
 
+namespace WebCore {
+class AccessibilityObject;
+}
+
 namespace WebKit {
 class WebDragData;
 class WebWorker;
@@ -169,6 +173,13 @@ class WebViewDelegate : virtual public WebWidgetDelegate {
     return true;
   }
 
+  // Called by ChromeClientImpl::focus() if accessibility on the renderer side
+  // is enabled, and a focus change has occurred. Will retrieve the id of the
+  // input AccessibilityObject and send it through IPC for handling on the
+  // browser side.
+  virtual void FocusAccessibilityObject(WebCore::AccessibilityObject* acc_obj) {
+  }
+
   // FrameLoaderClient -------------------------------------------------------
 
   // Notifies the delegate that a load has begun.
diff --git a/webkit/glue/webview_impl.h b/webkit/glue/webview_impl.h
index ae26890..caac1c8 100644
--- a/webkit/glue/webview_impl.h
+++ b/webkit/glue/webview_impl.h
@@ -138,6 +138,9 @@ class WebViewImpl : public WebView, public base::RefCounted<WebViewImpl> {
 
   WebCore::Frame* GetFocusedWebCoreFrame();
 
+  // Returns the currently focused Node or NULL if no node has focus.
+  WebCore::Node* GetFocusedNode();
+
   static WebViewImpl* FromPage(WebCore::Page* page);
 
   WebViewDelegate* delegate() {
@@ -285,9 +288,6 @@ class WebViewImpl : public WebView, public base::RefCounted<WebViewImpl> {
   WebCore::HitTestResult HitTestResultForWindowPos(
       const WebCore::IntPoint& pos);
 
-  // Returns the currently focused Node or NULL if no node has focus.
-  WebCore::Node* GetFocusedNode();
-
   // ImageResourceFetchers schedule via DownloadImage.
   std::set<ImageResourceFetcher*> image_fetchers_;