Add mouse input forwarding to gpu service

content/common/gpu/gpu_channel_manager.cc

Index: content/common/gpu/gpu_channel_manager.cc
diff --git a/content/common/gpu/gpu_channel_manager.cc b/content/common/gpu/gpu_channel_manager.cc
index a073e20151edce4dc033a6d9e54bf3c0196b214a..3c64bc28966f161a5e63cebfaf60604c43239c89 100644
--- a/content/common/gpu/gpu_channel_manager.cc
+++ b/content/common/gpu/gpu_channel_manager.cc
@@ -12,6 +12,7 @@
 #include "content/common/gpu/gpu_messages.h"
 #include "content/common/gpu/sync_point_manager.h"
 #include "content/common/message_router.h"
+#include "gpu/command_buffer/common/value_state.h"
 #include "gpu/command_buffer/service/feature_info.h"
 #include "gpu/command_buffer/service/gpu_switches.h"
 #include "gpu/command_buffer/service/mailbox_manager_impl.h"
@@ -162,6 +163,7 @@ bool GpuChannelManager::OnMessageReceived(const IPC::Message& msg) {
                         OnCreateViewCommandBuffer)
     IPC_MESSAGE_HANDLER(GpuMsg_DestroyGpuMemoryBuffer, OnDestroyGpuMemoryBuffer)
     IPC_MESSAGE_HANDLER(GpuMsg_LoadedShader, OnLoadedShader)
+    IPC_MESSAGE_HANDLER(GpuMsg_UpdateValueState, OnUpdateValueState)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
@@ -276,6 +278,16 @@ void GpuChannelManager::OnDestroyGpuMemoryBuffer(
   }
 }
 
+void GpuChannelManager::OnUpdateValueState(
+    int client_id, unsigned int target, const gpu::ValueState& state) {
+  // Only pass updated state to the channel corresponding to the
+  // render_widget_host where the event originated
+  GpuChannelMap::const_iterator iter = gpu_channels_.find(client_id);

[Ken Russell (switch to Gerrit), 2014/11/17 23:19:32]

Again it would be nicer if this didn't involve a search.

[orglofch, 2014/11/20 02:16:21]

Agreed, however, there doesn't appear to be another mechanism for associating
GpuChannels with RenderWidgetHosts outside of forwarding the data through the
renderer (which incurs latency).

[brianderson, 2014/11/20 21:11:26]

Seems okay to me. At least gpu_channels_ is a hash map, so performance should be
consistent regardless of the number of channels present.

+  if (iter != gpu_channels_.end()) {
+    iter->second->HandleUpdateValueState(target, state);
+  }
+}
+
 void GpuChannelManager::OnLoadedShader(std::string program_proto) {
   if (program_cache())
     program_cache()->LoadProgram(program_proto);