[Ozone-GBM] Add basic support for display configuration over IPC

ui/ozone/platform/dri/gpu_platform_support_gbm.cc

 // 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.
 
 #include "ui/ozone/platform/dri/gpu_platform_support_gbm.h"
 
 #include "ipc/ipc_message_macros.h"
 #include "ui/ozone/common/gpu/ozone_gpu_messages.h"
 #include "ui/ozone/platform/dri/dri_surface_factory.h"
 
 namespace ui {
 
 GpuPlatformSupportGbm::GpuPlatformSupportGbm(DriSurfaceFactory* dri)
     : sender_(NULL), dri_(dri) {
 }
 
+GpuPlatformSupportGbm::~GpuPlatformSupportGbm() {}
+
+void GpuPlatformSupportGbm::AddHandler(scoped_ptr<GpuPlatformSupport> handler) {
+  handlers_.push_back(handler.release());
+}
+
 void GpuPlatformSupportGbm::OnChannelEstablished(IPC::Sender* sender) {
   sender_ = sender;
+
+  for (size_t i = 0; i < handlers_.size(); ++i)
+    handlers_[i]->OnChannelEstablished(sender);
 }
 
 bool GpuPlatformSupportGbm::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
 
   IPC_BEGIN_MESSAGE_MAP(GpuPlatformSupportGbm, message)
   IPC_MESSAGE_HANDLER(OzoneGpuMsg_CursorSet, OnCursorSet)
   IPC_MESSAGE_HANDLER(OzoneGpuMsg_CursorMove, OnCursorMove)
   IPC_MESSAGE_UNHANDLED(handled = false);
   IPC_END_MESSAGE_MAP()
 
-  return handled;
+  if (!handled)
+    for (size_t i = 0; i < handlers_.size(); ++i)
+      if (handlers_[i]->OnMessageReceived(message))
+        return true;
+
+  return false;
 }
 
 void GpuPlatformSupportGbm::OnCursorSet(gfx::AcceleratedWidget widget,
                                         const SkBitmap& bitmap,
                                         const gfx::Point& location) {
   dri_->SetHardwareCursor(widget, bitmap, location);
 }
 
 void GpuPlatformSupportGbm::OnCursorMove(gfx::AcceleratedWidget widget,
                                          const gfx::Point& location) {
   dri_->MoveHardwareCursor(widget, location);
 }
 
 }  // namespace ui