Add flag to enable web content to invoke web intents.

chrome/browser/ui/browser.cc

 // Copyright (c) 2012 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/browser.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include <shellapi.h>
 #endif  // OS_WIN
@@ skipping 1638 matching lines @@
     const webkit_glue::WebIntentServiceData& data,
     bool user_gesture) {
   RegisterIntentHandlerHelper(web_contents, data, user_gesture);
 }
 
 void Browser::WebIntentDispatch(
     WebContents* web_contents,
     content::WebIntentsDispatcher* intents_dispatcher) {
   if (!web_intents::IsWebIntentsEnabledForProfile(profile_)) {
     web_intents::RecordIntentsDispatchDisabled();
+    delete intents_dispatcher;
     return;
   }
 
+  // Make sure the requester is coming from an extension/app page.
+  // Internal dispatches set |web_contents| to NULL.
+  if (web_contents &&
+      !CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kWebIntentsEnabledForWebContent)) {
+    ExtensionService* extensions_service = profile_->GetExtensionService();
+    if (!extensions_service ||
+        extensions_service->extensions()->GetExtensionOrAppIDByURL(
+            ExtensionURLInfo(web_contents->GetURL())).empty()) {
+      web_intents::RecordIntentsDispatchDisabled();
+      intents_dispatcher->SendReplyMessage(
+          webkit_glue::WEB_INTENT_REPLY_FAILURE,
+          ASCIIToUTF16("Intents may only be invoked from extensions/apps."));
+      return;
+    }
+  }
+
   web_intents::RecordIntentDispatchRequested();
 
   if (!web_contents) {
     // Intent is system-caused and the picker will show over the currently
     // active web contents.
     web_contents = chrome::GetActiveWebContents(this);
   }
   WebIntentPickerController* web_intent_picker_controller =
       WebIntentPickerController::FromWebContents(web_contents);
   web_intent_picker_controller->SetIntentsDispatcher(intents_dispatcher);
@@ skipping 641 matching lines @@
   if (contents && !allow_js_access) {
     contents->web_contents()->GetController().LoadURL(
         target_url,
         content::Referrer(),
         content::PAGE_TRANSITION_LINK,
         std::string());  // No extra headers.
   }
 
   return contents != NULL;
 }