Use a resource throttle to implement shouldOverrideUrlLoading.

android_webview/browser/renderer_host/aw_resource_dispatcher_host_delegate.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 "android_webview/browser/renderer_host/aw_resource_dispatcher_host_delegate.h"
 
 #include <string>
 
 #include "android_webview/browser/aw_contents_io_thread_client.h"
 #include "android_webview/browser/aw_login_delegate.h"
@@ skipping 208 matching lines @@
       content::ResourceRequestInfo::ForRequest(request);
 
   // We always push the throttles here. Checking the existence of io_client
   // is racy when a popup window is created. That is because RequestBeginning
   // is called whether or not requests are blocked via BlockRequestForRoute()
   // however io_client may or may not be ready at the time depending on whether
   // webcontents is created.
   throttles->push_back(new IoThreadClientThrottle(
       request_info->GetChildID(), request_info->GetRenderFrameID(), request));
 
-  // We allow intercepting only navigations within main frames. This
-  // is used to post onPageStarted. We handle shouldOverrideUrlLoading
-  // via a sync IPC.
-  if (resource_type == content::RESOURCE_TYPE_MAIN_FRAME) {
+  if (resource_type == content::RESOURCE_TYPE_MAIN_FRAME ||
+      (resource_type == content::RESOURCE_TYPE_SUB_FRAME &&
+       !request->url().SchemeIs(url::kHttpScheme) &&
+       !request->url().SchemeIs(url::kHttpsScheme) &&
+       !request->url().SchemeIs(url::kAboutScheme))) {
     throttles->push_back(InterceptNavigationDelegate::CreateThrottleFor(
         request));
-  } else {
+  }
+  if (resource_type != content::RESOURCE_TYPE_MAIN_FRAME)
     InterceptNavigationDelegate::UpdateUserGestureCarryoverInfo(request);
-  }
 }
 
 void AwResourceDispatcherHostDelegate::OnRequestRedirected(
     const GURL& redirect_url,
     net::URLRequest* request,
     content::ResourceContext* resource_context,
     content::ResourceResponse* response) {
   AddExtraHeadersIfNeeded(request, resource_context);
 }
 
@@ skipping 195 matching lines @@
       net::HttpRequestHeaders headers;
       headers.AddHeadersFromString(extra_headers);
       for (net::HttpRequestHeaders::Iterator it(headers); it.GetNext(); ) {
         request->SetExtraRequestHeaderByName(it.name(), it.value(), false);
       }
     }
   }
 }
 
 }  // namespace android_webview