Reland Track the active ExtensionKeybindingRegistry and make it available to EventRewriter.

chrome/browser/extensions/extension_commands_global_registry.cc

Index: chrome/browser/extensions/extension_commands_global_registry.cc
diff --git a/chrome/browser/extensions/extension_commands_global_registry.cc b/chrome/browser/extensions/extension_commands_global_registry.cc
index 1982addbe9c5be19b611a1cb0a0d9b452a797cab..a6016dd796734a3f33b444b58047ffb00e2979b5 100644
--- a/chrome/browser/extensions/extension_commands_global_registry.cc
+++ b/chrome/browser/extensions/extension_commands_global_registry.cc
@@ -16,7 +16,8 @@ ExtensionCommandsGlobalRegistry::ExtensionCommandsGlobalRegistry(
     : ExtensionKeybindingRegistry(context,
                                   ExtensionKeybindingRegistry::ALL_EXTENSIONS,
                                   NULL),
-      browser_context_(context) {
+      browser_context_(context),
+      registry_for_active_window_(NULL) {
   Init();
 }
 
@@ -58,6 +59,13 @@ void ExtensionCommandsGlobalRegistry::SetShortcutHandlingSuspended(
       suspended);
 }
 
+bool ExtensionCommandsGlobalRegistry::IsRegistered(
+    const ui::Accelerator& accelerator) {
+  return (registry_for_active_window() &&
+          registry_for_active_window()->IsAcceleratorRegistered(accelerator)) ||
+         IsAcceleratorRegistered(accelerator);
+}
+
 void ExtensionCommandsGlobalRegistry::AddExtensionKeybinding(
     const extensions::Extension* extension,
     const std::string& command_name) {