PageActions can now specify multiple icons and switch between them

using optional parameters to enableForTab.

BUG=http://crbug.com/11906
TEST=None

Review URL: http://codereview.chromium.org/149046

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@19772 0039d316-1c4b-4281-b951-d872f2087c98

18 files changed, 250 insertions, 67 deletions

diff --git a/chrome/browser/extensions/extension_page_actions_module.cc b/chrome/browser/extensions/extension_page_actions_module.cc
index 66bd9e3..d3ba09a 100644
--- a/chrome/browser/extensions/extension_page_actions_module.cc
+++ b/chrome/browser/extensions/extension_page_actions_module.cc
@@ -31,6 +31,18 @@ bool PageActionFunction::SetPageActionEnabled(bool enable) {
   std::string url;
   EXTENSION_FUNCTION_VALIDATE(action->GetString(keys::kUrlKey, &url));
 
+  std::string title;
+  int icon_id = 0;
+  if (enable) {
+    // Both of those are optional.
+    if (action->HasKey(keys::kTitleKey))
+      EXTENSION_FUNCTION_VALIDATE(action->GetString(keys::kTitleKey, &title));
+    if (action->HasKey(keys::kIconIdKey)) {
+      EXTENSION_FUNCTION_VALIDATE(action->GetInteger(keys::kIconIdKey,
+                                                     &icon_id));
+    }
+  }
+
   // Find the TabContents that contains this tab id.
   TabContents* contents = NULL;
   ExtensionTabUtil::GetTabById(tab_id, profile(), NULL, NULL, &contents, NULL);
@@ -66,7 +78,7 @@ bool PageActionFunction::SetPageActionEnabled(bool enable) {
   }
 
   // Set visibility and broadcast notifications that the UI should be updated.
-  contents->SetPageActionEnabled(page_action, enable);
+  contents->SetPageActionEnabled(page_action, enable, title, icon_id);
   contents->NotifyNavigationStateChanged(TabContents::INVALIDATE_PAGE_ACTIONS);
 
   return true;
diff --git a/chrome/browser/extensions/extension_page_actions_module_constants.cc b/chrome/browser/extensions/extension_page_actions_module_constants.cc
index e58264b..2b54f1b 100755
--- a/chrome/browser/extensions/extension_page_actions_module_constants.cc
+++ b/chrome/browser/extensions/extension_page_actions_module_constants.cc
@@ -8,6 +8,8 @@ namespace extension_page_actions_module_constants {
 
 const wchar_t kTabIdKey[] = L"tabId";
 const wchar_t kUrlKey[] = L"url";
+const wchar_t kTitleKey[] = L"title";
+const wchar_t kIconIdKey[] = L"iconId";
 
 const char kNoExtensionError[] = "No extension with id: *.";
 const char kNoTabError[] = "No tab with id: *.";
diff --git a/chrome/browser/extensions/extension_page_actions_module_constants.h b/chrome/browser/extensions/extension_page_actions_module_constants.h
index bf28b9f..91db0d8 100755
--- a/chrome/browser/extensions/extension_page_actions_module_constants.h
+++ b/chrome/browser/extensions/extension_page_actions_module_constants.h
@@ -12,6 +12,8 @@ namespace extension_page_actions_module_constants {
 // Keys.
 extern const wchar_t kTabIdKey[];
 extern const wchar_t kUrlKey[];
+extern const wchar_t kTitleKey[];
+extern const wchar_t kIconIdKey[];
 
 // Error messages.
 extern const char kNoExtensionError[];
diff --git a/chrome/browser/extensions/extensions_service.cc b/chrome/browser/extensions/extensions_service.cc
index df59e04..b44c630 100644
--- a/chrome/browser/extensions/extensions_service.cc
+++ b/chrome/browser/extensions/extensions_service.cc
@@ -753,12 +753,16 @@ Extension* ExtensionsServiceBackend::LoadExtension(
   for (PageActionMap::const_iterator i(page_actions.begin());
        i != page_actions.end(); ++i) {
     PageAction* page_action = i->second;
-    FilePath path = page_action->icon_path();
-    if (!file_util::PathExists(path)) {
-      ReportExtensionLoadError(extension_path,
-          StringPrintf("Could not load icon '%s' for page action.",
-          WideToUTF8(path.ToWStringHack()).c_str()));
-      return NULL;
+    const std::vector<FilePath>& icon_paths = page_action->icon_paths();
+    for (std::vector<FilePath>::const_iterator iter = icon_paths.begin();
+         iter != icon_paths.end(); ++iter) {
+      FilePath path = *iter;
+      if (!file_util::PathExists(path)) {
+        ReportExtensionLoadError(extension_path,
+            StringPrintf("Could not load icon '%s' for page action.",
+            WideToUTF8(path.ToWStringHack()).c_str()));
+        return NULL;
+      }
     }
   }
 
diff --git a/chrome/browser/extensions/extensions_service_unittest.cc b/chrome/browser/extensions/extensions_service_unittest.cc
index b195151..3b75dcc 100644
--- a/chrome/browser/extensions/extensions_service_unittest.cc
+++ b/chrome/browser/extensions/extensions_service_unittest.cc
@@ -40,7 +40,7 @@ const char* const good0 = "behllobkkfkfnphdnhnkndlbkcpglgmj";
 const char* const good1 = "hpiknbiabeeppbpihjehijgoemciehgk";
 const char* const good2 = "bjafgdebaacbbbecmhlhpofkepfkgcpa";
 const char* const good_crx = "ldnnhddmnhbkjipkidpdiheffobcpfmf";
-const char* const page_action = "kemkhnabegjkabakmlcaafgikalipenj";
+const char* const page_action = "obcimlgaoabeegjmmpldobjndiealpln";
 const char* const theme_crx = "iamefpfkojoapidjnbafmgkgncegbkad";
 const char* const theme2_crx = "pjpgmfcmabopnnfonnhmdjglfpjjfkbf";
 
@@ -654,7 +654,9 @@ TEST_F(ExtensionsServiceTest, CleanupOnStartup) {
   ASSERT_FALSE(file_util::PathExists(vers));
 }
 
-// Test installing extensions.
+// Test installing extensions. This test tries to install few extensions using
+// crx files. If you need to change those crx files, feel free to repackage
+// them, throw away the key used and change the id's above.
 TEST_F(ExtensionsServiceTest, InstallExtension) {
   InitializeEmptyExtensionsService();
 
@@ -690,6 +692,7 @@ TEST_F(ExtensionsServiceTest, InstallExtension) {
   // Bad signature.
   path = extensions_path.AppendASCII("bad_signature.crx");
   InstallExtension(path, false);
+  ValidatePrefKeyCount(pref_count);
 
   // 0-length extension file.
   path = extensions_path.AppendASCII("not_an_extension.crx");
diff --git a/chrome/browser/tab_contents/tab_contents.cc b/chrome/browser/tab_contents/tab_contents.cc
index c4906ce..0884317 100644
--- a/chrome/browser/tab_contents/tab_contents.cc
+++ b/chrome/browser/tab_contents/tab_contents.cc
@@ -565,23 +565,31 @@ void TabContents::SetIsCrashed(bool state) {
 }
 
 void TabContents::SetPageActionEnabled(const PageAction* page_action,
-                                       bool enable) {
+                                       bool enable,
+                                       const std::string& title,
+                                       int icon_id) {
   DCHECK(page_action);
 
-  if (enable == IsPageActionEnabled(page_action))
-    return;  // Don't need to do anything more.
+  if (!enable &&
+      enabled_page_actions_.end() == enabled_page_actions_.find(page_action)) {
+    return;  // Don't need to disable twice.
+  }
 
-  if (enable)
-    enabled_page_actions_.insert(page_action);
-  else
+  if (enable) {
+    enabled_page_actions_[page_action].reset(
+        new PageActionState(title, icon_id));
+  } else {
     enabled_page_actions_.erase(page_action);
+  }
 }
 
-bool TabContents::IsPageActionEnabled(const PageAction* page_action) {
-  DCHECK(page_action);
-  return enabled_page_actions_.end() != enabled_page_actions_.find(page_action);
-}
+const PageActionState* TabContents::GetPageActionState(
+    const PageAction* page_action) {
+  if (enabled_page_actions_.end() == enabled_page_actions_.find(page_action))
+    return NULL;
 
+  return enabled_page_actions_[page_action].get();
+}
 
 void TabContents::NotifyNavigationStateChanged(unsigned changed_flags) {
   if (delegate_)
diff --git a/chrome/browser/tab_contents/tab_contents.h b/chrome/browser/tab_contents/tab_contents.h
index 5b4fa7b..f81c725 100644
--- a/chrome/browser/tab_contents/tab_contents.h
+++ b/chrome/browser/tab_contents/tab_contents.h
@@ -32,6 +32,7 @@
 #include "chrome/common/gears_api.h"
 #include "chrome/common/navigation_types.h"
 #include "chrome/common/notification_registrar.h"
+#include "chrome/common/page_action.h"
 #include "chrome/common/property_bag.h"
 #include "chrome/common/renderer_preferences.h"
 #include "net/base/load_states.h"
@@ -254,10 +255,17 @@ class TabContents : public PageNavigator,
   void SetIsCrashed(bool state);
 
   // Adds/removes a page action to the list of page actions that are active in
+  // this tab. The parameter |title| (if not empty) can be used to override the
+  // page action title for this tab and |icon_id| specifies an icon index
+  // (defined in the manifest) to use instead of the first icon (for this tab).
+  void SetPageActionEnabled(const PageAction* page_action, bool enable,
+                            const std::string& title, int icon_id);
+
+  // Returns the page action state for this tab. The pair returns contains
+  // the title (string) for the page action and the icon index to use (int).
+  // If this function returns NULL it means the page action is not enabled for
   // this tab.
-  void SetPageActionEnabled(const PageAction* page_action, bool enable);
-  // Checks to see if the PageAction should be visible in this tab.
-  bool IsPageActionEnabled(const PageAction* page_action);
+  const PageActionState* GetPageActionState(const PageAction* page_action);
 
   // Whether the tab is in the process of being destroyed.
   // Added as a tentative work-around for focus related bug #4633.  This allows
@@ -1036,10 +1044,12 @@ class TabContents : public PageNavigator,
 
   // Data for Page Actions -----------------------------------------------------
 
-  // A set of page actions that are enabled in this tab. This list is cleared
-  // every time the mainframe navigates and populated by the PageAction
-  // extension API.
-  std::set<const PageAction*> enabled_page_actions_;
+  // A map of page actions that are enabled in this tab (and a state object
+  // that can be used to override the title and icon used for the page action).
+  // This map is cleared every time the mainframe navigates and populated by the
+  // PageAction extension API.
+  std::map< const PageAction*, linked_ptr<PageActionState> >
+      enabled_page_actions_;
 
   // Data for misc internal state ----------------------------------------------
 
diff --git a/chrome/browser/views/location_bar_view.cc b/chrome/browser/views/location_bar_view.cc
index 7530dee..af8c57f 100644
--- a/chrome/browser/views/location_bar_view.cc
+++ b/chrome/browser/views/location_bar_view.cc
@@ -1140,7 +1140,8 @@ void LocationBarView::SecurityImageView::ShowInfoBubble() {
 class LocationBarView::PageActionImageView::ImageLoadingTracker
   : public base::RefCountedThreadSafe<ImageLoadingTracker> {
  public:
-  explicit ImageLoadingTracker(PageActionImageView* view) : view_(view) {
+  explicit ImageLoadingTracker(PageActionImageView* view, int image_count)
+    : view_(view), image_count_(image_count) {
     AddRef();  // We hold on to a reference to ourself to make sure we don't
                // get deleted until we get a response from image loading (see
                // ImageLoadingDone).
@@ -1151,16 +1152,20 @@ class LocationBarView::PageActionImageView::ImageLoadingTracker
     view_ = NULL;
   }
 
-  void OnImageLoaded(SkBitmap* image) {
-    view_->OnImageLoaded(image);
+  void OnImageLoaded(SkBitmap* image, int index) {
+    view_->OnImageLoaded(image, index);
     delete image;
-    Release();  // We are no longer needed.
+    if (--image_count_ == 0)
+      Release();  // We are no longer needed.
   }
 
  private:
 
   // The view that is waiting for the image to load.
   PageActionImageView* view_;
+
+  // The number of images this ImageTracker should keep track of.
+  int image_count_;
 };
 
 // The LoadImageTask is for asynchronously loading the image on the file thread.
@@ -1168,16 +1173,24 @@ class LocationBarView::PageActionImageView::ImageLoadingTracker
 // |callback_loop| to let the caller know the image is done loading.
 class LocationBarView::PageActionImageView::LoadImageTask : public Task {
  public:
+  // Constructor for the LoadImageTask class. |tracker| is the object that
+  // we use to communicate back to the entity that wants the image after we
+  // decode it. |path| is the path to load the image from. |index| is an
+  // identifier for the image that we pass back to the caller.
   LoadImageTask(ImageLoadingTracker* tracker,
-                const FilePath& path)
+                const FilePath& path,
+                int index)
     : callback_loop_(MessageLoop::current()),
       tracker_(tracker),
-      path_(path) {}
+      path_(path),
+      index_(index) {}
 
   void ReportBack(SkBitmap* image) {
     DCHECK(image);
     callback_loop_->PostTask(FROM_HERE, NewRunnableMethod(tracker_,
-        &PageActionImageView::ImageLoadingTracker::OnImageLoaded, image));
+        &PageActionImageView::ImageLoadingTracker::OnImageLoaded,
+        image,
+        index_));
   }
 
   virtual void Run() {
@@ -1223,6 +1236,9 @@ class LocationBarView::PageActionImageView::LoadImageTask : public Task {
 
   // The path to the image to load asynchronously.
   FilePath path_;
+
+  // The index of the icon being loaded.
+  int index_;
 };
 
 LocationBarView::PageActionImageView::PageActionImageView(
@@ -1233,15 +1249,22 @@ LocationBarView::PageActionImageView::PageActionImageView(
       owner_(owner),
       profile_(profile),
       page_action_(page_action),
-      tracker_(new ImageLoadingTracker(this)) {
+      current_tab_id_(-1),
+      tooltip_(page_action_->name()) {
   // Load the images this view needs asynchronously on the file thread. We'll
   // get a call back into OnImageLoaded if the image loads successfully. If not,
   // the ImageView will have no image and will not appear in the Omnibox.
-  DCHECK(!page_action->icon_path().empty());
-  FilePath path = FilePath(page_action->icon_path());
+  DCHECK(!page_action->icon_paths().empty());
+  const std::vector<FilePath>& icon_paths = page_action->icon_paths();
+  page_action_icons_.resize(icon_paths.size());
+  int index = 0;
   MessageLoop* file_loop = g_browser_process->file_thread()->message_loop();
-  file_loop->PostTask(FROM_HERE,
-      new LoadImageTask(tracker_, page_action->icon_path()));
+  tracker_ = new ImageLoadingTracker(this, icon_paths.size());
+  for (std::vector<FilePath>::const_iterator iter = icon_paths.begin();
+       iter != icon_paths.end(); ++iter) {
+    FilePath path = *iter;
+    file_loop->PostTask(FROM_HERE, new LoadImageTask(tracker_, path, index++));
+  }
 }
 
 LocationBarView::PageActionImageView::~PageActionImageView() {
@@ -1259,7 +1282,7 @@ bool LocationBarView::PageActionImageView::OnMousePressed(
 
 void LocationBarView::PageActionImageView::ShowInfoBubble() {
   SkColor text_color = SK_ColorBLACK;
-  ShowInfoBubbleImpl(ASCIIToWide(page_action_->name()), text_color);
+  ShowInfoBubbleImpl(ASCIIToWide(tooltip_), text_color);
 }
 
 void LocationBarView::PageActionImageView::UpdateVisibility(
@@ -1269,12 +1292,30 @@ void LocationBarView::PageActionImageView::UpdateVisibility(
   current_tab_id_ = ExtensionTabUtil::GetTabId(contents);
   current_url_ = url;
 
-  SetVisible(contents->IsPageActionEnabled(page_action_));
+  const PageActionState* state = contents->GetPageActionState(page_action_);
+  bool visible = state != NULL;
+  if (visible) {
+    // Set the tooltip.
+    if (state->title().empty())
+      tooltip_ = page_action_->name();
+    else
+      tooltip_ = state->title();
+    // Set the image.
+    int index = state->icon_index();
+    // The image index (if not within bounds) will be set to the first image.
+    if (index < 0 || index >= static_cast<int>(page_action_icons_.size()))
+      index = 0;
+    ImageView::SetImage(page_action_icons_[index]);
+  }
+  SetVisible(visible);
 }
 
-void LocationBarView::PageActionImageView::OnImageLoaded(SkBitmap* image) {
-  tracker_ = NULL;  // The tracker object will delete itself when we return.
-  ImageView::SetImage(image);
+void LocationBarView::PageActionImageView::OnImageLoaded(SkBitmap* image,
+                                                         size_t index) {
+  DCHECK(index < page_action_icons_.size());
+  if (index == page_action_icons_.size() - 1)
+    tracker_ = NULL;  // The tracker object will delete itself when we return.
+  page_action_icons_[index] = *image;
   owner_->UpdatePageActions();
 }
 
diff --git a/chrome/browser/views/location_bar_view.h b/chrome/browser/views/location_bar_view.h
index b90693f..97e7eb6 100644
--- a/chrome/browser/views/location_bar_view.h
+++ b/chrome/browser/views/location_bar_view.h
@@ -332,7 +332,7 @@ class LocationBarView : public LocationBar,
     void UpdateVisibility(TabContents* contents, GURL url);
 
     // A callback for when the image has loaded.
-    void OnImageLoaded(SkBitmap* image);
+    void OnImageLoaded(SkBitmap* image, size_t index);
 
   private:
     // We load the images for the PageActions on the file thread. These tasks
@@ -350,6 +350,9 @@ class LocationBarView : public LocationBar,
     // us, it resides in the extension of this particular profile.
     const PageAction* page_action_;
 
+    // The icons representing different states for the page action.
+    std::vector<SkBitmap> page_action_icons_;
+
     // The object that is waiting for the image loading to complete
     // asynchronously.
     ImageLoadingTracker* tracker_;
@@ -360,6 +363,9 @@ class LocationBarView : public LocationBar,
     // The URL we are currently showing the icon for.
     GURL current_url_;
 
+    // The string to show for a tooltip;
+    std::string tooltip_;
+
     DISALLOW_COPY_AND_ASSIGN(PageActionImageView);
   };
 
diff --git a/chrome/common/extensions/extension.cc b/chrome/common/extensions/extension.cc
index 33baff8..6bce681 100644
--- a/chrome/common/extensions/extension.cc
+++ b/chrome/common/extensions/extension.cc
@@ -55,6 +55,7 @@ const wchar_t* Extension::kContentScriptsKey = L"content_scripts";
 const wchar_t* Extension::kCssKey = L"css";
 const wchar_t* Extension::kDescriptionKey = L"description";
 const wchar_t* Extension::kIconPathKey = L"icon";
+const wchar_t* Extension::kIconPathsKey = L"icons";
 const wchar_t* Extension::kJsKey = L"js";
 const wchar_t* Extension::kMatchesKey = L"matches";
 const wchar_t* Extension::kNameKey = L"name";
@@ -126,10 +127,12 @@ const char* Extension::kInvalidNameError =
     "Required value 'name' is missing or invalid.";
 const char* Extension::kInvalidPageActionError =
     "Invalid value for 'page_actions[*]'.";
+const char* Extension::kInvalidPageActionIconPathError =
+    "Invalid value for 'page_actions[*].icons[*]'.";
 const char* Extension::kInvalidPageActionsListError =
     "Invalid value for 'page_actions'.";
-const char* Extension::kInvalidPageActionIconPathError =
-    "Invalid value for 'page_actions[*].icon'.";
+const char* Extension::kInvalidPageActionIconPathsError =
+    "Required value 'page_actions[*].icons' is missing or invalid.";
 const char* Extension::kInvalidPageActionIdError =
     "Required value 'id' is missing or invalid.";
 const char* Extension::kInvalidPageActionTypeValueError =
@@ -398,15 +401,31 @@ PageAction* Extension::LoadPageActionHelper(
   scoped_ptr<PageAction> result(new PageAction());
   result->set_extension_id(id());
 
-  // Read the page action |icon|.
-  std::string icon;
-  if (!page_action->GetString(kIconPathKey, &icon)) {
+  ListValue* icons;
+  // Read the page action |icons|.
+  if (!page_action->HasKey(kIconPathsKey) ||
+      !page_action->GetList(kIconPathsKey, &icons) ||
+      icons->GetSize() == 0) {
     *error = ExtensionErrorUtils::FormatErrorMessage(
-        kInvalidPageActionIconPathError, IntToString(definition_index));
+        kInvalidPageActionIconPathsError, IntToString(definition_index));
     return NULL;
   }
-  FilePath icon_path = path_.AppendASCII(icon);
-  result->set_icon_path(icon_path);
+
+  int icon_count = 0;
+  for (ListValue::const_iterator iter = icons->begin();
+       iter != icons->end(); ++iter) {
+    FilePath::StringType path;
+    if (!(*iter)->GetAsString(&path) || path.empty()) {
+      *error = ExtensionErrorUtils::FormatErrorMessage(
+          kInvalidPageActionIconPathError,
+          IntToString(definition_index), IntToString(icon_count));
+      return NULL;
+    }
+
+    FilePath icon_path = path_.Append(path);
+    result->AddIconPath(icon_path);
+    ++icon_count;
+  }
 
   // Read the page action |id|.
   std::string id;
@@ -504,7 +523,7 @@ FilePath Extension::GetResourcePath(const FilePath& extension_path,
   return ret_val;
 }
 
-Extension::Extension(const FilePath& path) {
+Extension::Extension(const FilePath& path) : is_theme_(false) {
   DCHECK(path.IsAbsolute());
   location_ = INVALID;
 
@@ -939,7 +958,11 @@ std::set<FilePath> Extension::GetBrowserImages() {
 
   for (PageActionMap::const_iterator it = page_actions().begin();
        it != page_actions().end(); ++it) {
-    image_paths.insert(it->second->icon_path());
+    const std::vector<FilePath>& icon_paths = it->second->icon_paths();
+    for (std::vector<FilePath>::const_iterator iter = icon_paths.begin();
+         iter != icon_paths.end(); ++iter) {
+      image_paths.insert(*iter);
+    }
   }
 
   return image_paths;
diff --git a/chrome/common/extensions/extension.h b/chrome/common/extensions/extension.h
index ec14b0b..1705e12 100644
--- a/chrome/common/extensions/extension.h
+++ b/chrome/common/extensions/extension.h
@@ -60,6 +60,7 @@ class Extension {
   static const wchar_t* kCssKey;
   static const wchar_t* kDescriptionKey;
   static const wchar_t* kIconPathKey;
+  static const wchar_t* kIconPathsKey;
   static const wchar_t* kJsKey;
   static const wchar_t* kMatchesKey;
   static const wchar_t* kNameKey;
@@ -115,6 +116,7 @@ class Extension {
   static const char* kInvalidPageActionError;
   static const char* kInvalidPageActionsListError;
   static const char* kInvalidPageActionIconPathError;
+  static const char* kInvalidPageActionIconPathsError;
   static const char* kInvalidPageActionIdError;
   static const char* kInvalidPageActionTypeValueError;
   static const char* kInvalidPermissionsError;
diff --git a/chrome/common/page_action.h b/chrome/common/page_action.h
index d9ccfea..3331f8e 100644
--- a/chrome/common/page_action.h
+++ b/chrome/common/page_action.h
@@ -5,8 +5,9 @@
 #ifndef CHROME_COMMON_PAGE_ACTION_H_
 #define CHROME_COMMON_PAGE_ACTION_H_
 
-#include <string>
 #include <map>
+#include <string>
+#include <vector>
 
 #include "base/file_path.h"
 
@@ -34,9 +35,9 @@ class PageAction {
   std::string name() const { return name_; }
   void set_name(const std::string& name) { name_ = name; }
 
-  FilePath icon_path() const { return icon_path_; }
-  void set_icon_path(const FilePath& icon_path) {
-    icon_path_ = icon_path;
+  const std::vector<FilePath>& icon_paths() const { return icon_paths_; }
+  void AddIconPath(const FilePath& icon_path) {
+    icon_paths_.push_back(icon_path);
   }
 
  private:
@@ -53,10 +54,31 @@ class PageAction {
   // The name of the PageAction.
   std::string name_;
 
-  // The icon that represents the PageIcon.
-  FilePath icon_path_;
+  // The paths to the icons that this PageIcon can show.
+  std::vector<FilePath> icon_paths_;
 };
 
 typedef std::map<std::string, PageAction*> PageActionMap;
 
+// This class keeps track of what values each tab uses to override the default
+// values of the PageAction.
+class PageActionState {
+ public:
+  PageActionState(std::string title, int icon_index)
+    : title_(title), icon_index_(icon_index) {
+  }
+
+  std::string title() const { return title_; }
+  int icon_index() const { return icon_index_; }
+
+ private:
+  // The title to use.
+  std::string title_;
+
+  // The icon to use.
+  int icon_index_;
+
+  DISALLOW_COPY_AND_ASSIGN(PageActionState);
+};
+
 #endif  // CHROME_COMMON_PAGE_ACTION_H_
diff --git a/chrome/renderer/renderer_resources.grd b/chrome/renderer/renderer_resources.grd
index c59e98c..cda253b 100644
--- a/chrome/renderer/renderer_resources.grd
+++ b/chrome/renderer/renderer_resources.grd
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!-- This comment is only here because changes to resources are not picked up
-without changes to the corresponding grd file.  -->
+without changes to the corresponding grd file. -->
 <grit latest_public_release="0" current_release="1">
   <outputs>
     <output filename="grit/renderer_resources.h" type="rc_header">
diff --git a/chrome/renderer/resources/extension_process_bindings.js b/chrome/renderer/resources/extension_process_bindings.js
index 8b4c4bb..2e76723 100644
--- a/chrome/renderer/resources/extension_process_bindings.js
+++ b/chrome/renderer/resources/extension_process_bindings.js
@@ -320,7 +320,9 @@ var chrome = chrome || {};
       type: "object",
       properties: {
         tabId: chrome.types.pInt,
-        url: chrome.types.str
+        url: chrome.types.str,
+        title: chrome.types.optStr,
+        iconId: chrome.types.optPInt,
       },
       optional: false
     }
diff --git a/chrome/test/data/extensions/page_action.crx b/chrome/test/data/extensions/page_action.crx
index 2a397c8..7420c32 100644
--- a/chrome/test/data/extensions/page_action.crx
+++ b/chrome/test/data/extensions/page_action.crx
diff --git a/chrome/test/data/extensions/samples/subscribe_page_action/background.html b/chrome/test/data/extensions/samples/subscribe_page_action/background.html
index e85e5a6..0eeca7e 100644
--- a/chrome/test/data/extensions/samples/subscribe_page_action/background.html
+++ b/chrome/test/data/extensions/samples/subscribe_page_action/background.html
@@ -1,8 +1,13 @@
 <html>
+<head>
 <script>
   // The Page Action ID.
   var pageActionId = "RssPageAction";
 
+  // The icons to use. These correspond to the icons listed in the manifest.
+  var subscribeId = 0;
+  var alreadySubscribedId = 1;
+
   // The window this Page Action is associated with.
   var windowId = -1;
 
@@ -15,6 +20,32 @@
   // The feed URL found on the page.
   var feedUrl = "";
 
+  // The URL to use to check if user is subscribed already.
+  var subscribedUrl = "http://www.google.com/reader/api/0/subscribed?s=feed%2F";
+
+  // The XMLHttpRequest object that checks if you are already subscribed.
+  var req;
+
+  // The status of whether you have already subscribed to this feed or not.
+  var alreadySubscribed = false;
+
+  function EnableIcon(subscribed) {
+    alreadySubscribed = subscribed;
+    if (!alreadySubscribed) {
+      chrome.pageActions.enableForTab(
+        pageActionId, {tabId: tabId,
+                       url: pageUrl,
+                       title: "Click to subscribe...",
+                       iconId: subscribeId});
+    } else {
+      chrome.pageActions.enableForTab(
+        pageActionId, {tabId: tabId,
+                       url: pageUrl,
+                       title: "You are already subscribed to this feed",
+                       iconId: alreadySubscribedId});
+    }
+  }
+
   chrome.self.onConnect.addListener(function(port) {
     windowId = port.tab.windowId;
     tabId = port.tab.id;
@@ -28,17 +59,29 @@
       // Let Chrome know that the PageAction needs to be enabled for this tabId
       // and for the url of this page.
       if (feedUrl) {
-        chrome.pageActions.enableForTab(pageActionId,
-                                        {tabId: tabId, url: pageUrl});
+        EnableIcon(false);  // Not subscribed (as far as we know, might change).
+
+        // But also check the server to see if we have already subscribed so
+        // that we can update the status.
+        feedUrl = encodeURIComponent(feedUrl);
+        req = new XMLHttpRequest();
+        req.onload = handleResponse;
+        req.open("GET", subscribedUrl + feedUrl, false);
+        req.send(null);
       }
     });
   });
 
+  function handleResponse() {
+    if (req.responseText == "true")
+      EnableIcon(true);  // true == Already suscribed.
+  }
+
   // Chrome will call into us when the user clicks on the icon in the OmniBox.
   chrome.pageActions.onExecute.addListener(function(reply) {
     chrome.windows.getCurrent(function(window) {
       chrome.tabs.get(reply.data.tabId, function(tab) {
-        if (window.focused) {
+        if (!alreadySubscribed && window.focused) {
           // We need to know if we are the active window, because the tab may
           // have moved to another window and we don't want to execute this
           // action multiple times.
@@ -46,7 +89,6 @@
               reply.data.tabUrl == pageUrl) {
             // Create a new tab showing the subscription page with the right
             // feed URL.
-            var url = "http://www.google.com/reader/view/feed/" + feedUrl;
             chrome.tabs.create({url: "subscribe.html?" + feedUrl,
                                windowId: windowId});
           }
@@ -55,4 +97,5 @@
     });
   });
 </script>
+</head>
 </html>
diff --git a/chrome/test/data/extensions/samples/subscribe_page_action/feed-icon-16x16-subscribed.png b/chrome/test/data/extensions/samples/subscribe_page_action/feed-icon-16x16-subscribed.png
new file mode 100644
index 0000000..0369a6b37
--- /dev/null
+++ b/chrome/test/data/extensions/samples/subscribe_page_action/feed-icon-16x16-subscribed.png
diff --git a/chrome/test/data/extensions/samples/subscribe_page_action/manifest.json b/chrome/test/data/extensions/samples/subscribe_page_action/manifest.json
index 9c34a50..6a8f225 100644
--- a/chrome/test/data/extensions/samples/subscribe_page_action/manifest.json
+++ b/chrome/test/data/extensions/samples/subscribe_page_action/manifest.json
@@ -16,7 +16,10 @@
     {
       "id": "RssPageAction",
       "name": "Subscribe to this feed",
-      "icon": "feed-icon-16x16.png"
+      "icons": [
+         "feed-icon-16x16.png",
+         "feed-icon-16x16-subscribed.png"
+      ]
     }
   ]
 }
\ No newline at end of file