[Cronet] Hook up library loader, system proxy and network change notifier to async api.

components/cronet/android/cronet_url_request_adapter.h

 // Copyright 2014 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 COMPONENTS_CRONET_ANDROID_CRONET_URL_REQUEST_ADAPTER_H_
 #define COMPONENTS_CRONET_ANDROID_CRONET_URL_REQUEST_ADAPTER_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 65 matching lines @@
   void set_method(const std::string& method) {
     initial_method_ = method;
   }
 
   // Adds a header to the request before it starts.
   void AddRequestHeader(const std::string& name, const std::string& value);
 
   // Methods called on any thread.
 
   // Posts tasks to network thread.
-  bool PostTaskToNetworkThread(const tracked_objects::Location& from_here,
+  void PostTaskToNetworkThread(const tracked_objects::Location& from_here,
                                const base::Closure& task);
 
   // Returns true if called on network thread.
   bool IsOnNetworkThread() const;
 
   // Methods called only on network thread.
 
   // Starts the request.
   void Start();
 
@@ skipping 51 matching lines @@
 
   scoped_refptr<net::IOBufferWithSize> read_buffer_;
   scoped_ptr<net::URLRequest> url_request_;
 
   DISALLOW_COPY_AND_ASSIGN(CronetURLRequestAdapter);
 };
 
 }  // namespace cronet
 
 #endif  // COMPONENTS_CRONET_ANDROID_CRONET_URL_REQUEST_ADAPTER_H_