Place <webview> tag behind a flag.

chrome/renderer/chrome_content_renderer_client.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/renderer/chrome_content_renderer_client.h"
 
 #include <string>
 #include <vector>
 
 #include "base/command_line.h"
@@ skipping 309 matching lines @@
     const WebPluginParams& params,
     WebPlugin** plugin) {
   std::string orig_mime_type = params.mimeType.utf8();
   if (orig_mime_type == content::kBrowserPluginMimeType) {
     if (CommandLine::ForCurrentProcess()->HasSwitch(
         switches::kEnableBrowserPluginForAllViewTypes))
       return false;
     WebDocument document = frame->document();
     const extensions::Extension* extension =
         GetExtension(document.securityOrigin());
-    if (extension && extension->HasAPIPermission(
-        extensions::APIPermission::kWebView))
+    if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kEnableWebView) &&
+        extension &&
+        extension->HasAPIPermission(extensions::APIPermission::kWebView))
       return false;
   }
 
   ChromeViewHostMsg_GetPluginInfo_Output output;
   render_view->Send(new ChromeViewHostMsg_GetPluginInfo(
       render_view->GetRoutingID(), GURL(params.url),
       frame->top()->document().url(), orig_mime_type, &output));
   *plugin = CreatePlugin(render_view, frame, params, output);
   return true;
 }
@@ skipping 644 matching lines @@
 bool ChromeContentRendererClient::IsOtherExtensionWithWebRequestInstalled() {
   return extension_dispatcher_->IsOtherExtensionWithWebRequestInstalled();
 }
 
 void ChromeContentRendererClient::RegisterPPAPIInterfaceFactories(
     webkit::ppapi::PpapiInterfaceFactoryManager* factory_manager) {
   factory_manager->RegisterFactory(ChromePPAPIInterfaceFactory);
 }
 
 }  // namespace chrome