Only deliver extension messages to contexts that care.

chrome/renderer/extensions/extension_dispatcher.cc

Index: chrome/renderer/extensions/extension_dispatcher.cc
diff --git a/chrome/renderer/extensions/extension_dispatcher.cc b/chrome/renderer/extensions/extension_dispatcher.cc
index 7e92b53690b4f6b1eb8739c1c0c7c23f90f06fc1..e15f55df81899c60cd4a44c848301ed904ff37bc 100644
--- a/chrome/renderer/extensions/extension_dispatcher.cc
+++ b/chrome/renderer/extensions/extension_dispatcher.cc
@@ -60,6 +60,7 @@ bool ExtensionDispatcher::OnControlMessageReceived(
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(ExtensionDispatcher, message)
     IPC_MESSAGE_HANDLER(ExtensionMsg_MessageInvoke, OnMessageInvoke)
+    IPC_MESSAGE_HANDLER(ExtensionMsg_DeliverMessage, OnDeliverMessage)
     IPC_MESSAGE_HANDLER(ExtensionMsg_SetFunctionNames, OnSetFunctionNames)
     IPC_MESSAGE_HANDLER(ExtensionMsg_Loaded, OnLoaded)
     IPC_MESSAGE_HANDLER(ExtensionMsg_Unloaded, OnUnloaded)
@@ -142,6 +143,13 @@ void ExtensionDispatcher::OnMessageInvoke(const std::string& extension_id,
   }
 }
 
+void ExtensionDispatcher::OnDeliverMessage(int target_port_id,
+                                           const std::string& message) {
+  RendererExtensionBindings::DeliverMessage(target_port_id,
+                                            message,
+                                            NULL);  // All render views.
+}
+
 void ExtensionDispatcher::OnLoaded(const ExtensionMsg_Loaded_Params& params) {
   scoped_refptr<const Extension> extension(params.ConvertToExtension());
   if (!extension) {