Implement a ResourceThrottle for URL overriding in Chrome on Android.

chrome/browser/renderer_host/intercept_navigation_resource_throttle.h

Index: chrome/browser/renderer_host/intercept_navigation_resource_throttle.h
diff --git a/chrome/browser/renderer_host/intercept_navigation_resource_throttle.h b/chrome/browser/renderer_host/intercept_navigation_resource_throttle.h
new file mode 100644
index 0000000000000000000000000000000000000000..6877a6227f283713af06c7876deb486412f46464
--- /dev/null
+++ b/chrome/browser/renderer_host/intercept_navigation_resource_throttle.h
@@ -0,0 +1,41 @@
+// 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.
+
+#ifndef CHROME_BROWSER_RENDERER_HOST_INTERCEPT_NAVIGATION_RESOURCE_THROTTLE_H_
+#define CHROME_BROWSER_RENDERER_HOST_INTERCEPT_NAVIGATION_RESOURCE_THROTTLE_H_
+#pragma once
+
+#include <string>
+
+#include "base/memory/weak_ptr.h"
+#include "content/public/browser/resource_throttle.h"
+
+namespace net {
+class URLRequest;
+}  // namespace net
+
+// This class allows the embedder (via WebContentsDelegate) to selectively
+// ignore top level navigations.
+class InterceptNavigationResourceThrottle
+    : public content::ResourceThrottle {
+ public:
+  explicit InterceptNavigationResourceThrottle(net::URLRequest* request);
+  virtual ~InterceptNavigationResourceThrottle();
+
+  // content::ResourceThrottle implementation:
+  virtual void WillStartRequest(bool* defer) OVERRIDE;
+  virtual void WillRedirectRequest(const GURL& new_url, bool* defer) OVERRIDE;
+
+ private:
+  bool ShouldDeferRequestForURL(const GURL& url);
+  void OnResultObtained(bool should_ignore_navigation);
+
+  net::URLRequest* request_;
+  base::WeakPtrFactory<InterceptNavigationResourceThrottle>
+      weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(InterceptNavigationResourceThrottle);
+};
+
+#endif  // CHROME_BROWSER_RENDERER_HOST_INTERCEPT_NAVIGATION_RESOURCE_THROTTLE_H_