Add a Content API around BrowserChildProcessHost, similar to what was done with ChildProcessHost....

chrome/browser/ui/webui/options/chromeos/user_image_source.cc

 // Copyright (c) 2011 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/webui/options/chromeos/user_image_source.h"
 
 #include "base/memory/ref_counted_memory.h"
+#include "base/message_loop.h"
 #include "chrome/browser/chromeos/login/user_manager.h"
 #include "chrome/common/url_constants.h"
 #include "grit/theme_resources.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/codec/png_codec.h"
 
 namespace chromeos {
 
 std::vector<unsigned char> UserImageSource::GetUserImage(
     const std::string& email) const {
@@ skipping 26 matching lines @@
   SendResponse(request_id, new RefCountedBytes(GetUserImage(email)));
 }
 
 std::string UserImageSource::GetMimeType(const std::string&) const {
   // We need to explicitly return a mime type, otherwise if the user tries to
   // drag the image they get no extension.
   return "image/png";
 }
 
 }  // namespace chromeos