Track the active ExtensionKeybindingRegistry and make it available to EventRewriter.

chrome/browser/ui/views/toolbar/toolbar_view.cc

 // Copyright 2013 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 "chrome/browser/ui/views/toolbar/toolbar_view.h"
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/i18n/number_formatting.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/app/chrome_command_ids.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/command_updater.h"
+#include "chrome/browser/extensions/extension_commands_global_registry.h"
 #include "chrome/browser/extensions/extension_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/themes/theme_service.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_command_controller.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/browser_content_setting_bubble_model_delegate.h"
 #include "chrome/browser/ui/browser_instant_controller.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
 #include "chrome/browser/ui/browser_window.h"
@@ skipping 236 matching lines @@
           IsAccessibleBrowser()) {
     back_->SetTooltipText(
         l10n_util::GetStringUTF16(IDS_ACCNAME_TOOLTIP_BACK));
     forward_->SetTooltipText(
         l10n_util::GetStringUTF16(IDS_ACCNAME_TOOLTIP_FORWARD));
   }
 }
 
 void ToolbarView::OnWidgetVisibilityChanged(views::Widget* widget,
                                             bool visible) {
-  // Safe to call multiple times; the bubble will only appear once.
-  if (visible)
+  extensions::ExtensionKeybindingRegistry* registry = NULL;
+
+  if (visible) {
+    // Safe to call multiple times; the bubble will only appear once.
     extension_message_bubble_factory_->MaybeShow(app_menu_);
+    registry = browser_actions_->extension_keybinding_registry();
+  }
+
+  extensions::ExtensionCommandsGlobalRegistry::Get(browser_->profile())
+      ->set_active_registry(registry);

[Devlin, 2014/09/12 00:10:33]

Not quite.  We should only set this to NULL if we *were* the active registry. 
Something like:

ExtensionCommandsGlobalRegistry* global_command_registry =
    ExtensionCommandsGlobalRegistry::Get(browser_->profile());
if (visible) {
  extension_message_bubble_factory_->MaybeShow(app_menu_);
  global_command_registry->set_active_registry(
      browser_actions_->extension_keybinding_registry());
} else if (global_command_registry->active_registry() ==
               browser_actions_->extension_keybinding_registry()) {
  global_command_registry->set_active_registry(NULL);
}

The point is to set the registry to NULL if and only if this *was* the active
registry to begin with (otherwise, the currently-active registry will still be
valid).

Same goes for OnWidgetDestroyed() code.

[David Tseng, 2014/09/12 01:26:58]

Yup; you're totally right. Done.

+}
+
+void ToolbarView::OnWidgetDestroyed(views::Widget* widget) {
+  extensions::ExtensionCommandsGlobalRegistry::Get(browser_->profile())
+      ->set_active_registry(NULL);
 }
 
 void ToolbarView::Update(WebContents* tab) {
   if (location_bar_)
     location_bar_->Update(tab);
   if (browser_actions_)
     browser_actions_->RefreshBrowserActionViews();
   if (reload_)
     reload_->set_menu_enabled(chrome::IsDebuggerAttachedToCurrentTab(browser_));
 }
@@ skipping 480 matching lines @@
 
 void ToolbarView::OnShowHomeButtonChanged() {
   Layout();
   SchedulePaint();
 }
 
 int ToolbarView::content_shadow_height() const {
   return browser_->host_desktop_type() == chrome::HOST_DESKTOP_TYPE_ASH ?
       kContentShadowHeightAsh : kContentShadowHeight;
 }