gpu: Remove Echo and SwapCompletion GL interfacess

content/common/gpu/client/command_buffer_proxy_impl.cc

Index: content/common/gpu/client/command_buffer_proxy_impl.cc
diff --git a/content/common/gpu/client/command_buffer_proxy_impl.cc b/content/common/gpu/client/command_buffer_proxy_impl.cc
index 20802095797e8caed3a52408a98af04723cfce7f..a0f67b3dedb55955c6cbb71f0bea71a06cc660b0 100644
--- a/content/common/gpu/client/command_buffer_proxy_impl.cc
+++ b/content/common/gpu/client/command_buffer_proxy_impl.cc
@@ -42,7 +42,6 @@ bool CommandBufferProxyImpl::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(CommandBufferProxyImpl, message)
     IPC_MESSAGE_HANDLER(GpuCommandBufferMsg_Destroyed, OnDestroyed);
-    IPC_MESSAGE_HANDLER(GpuCommandBufferMsg_EchoAck, OnEchoAck);
     IPC_MESSAGE_HANDLER(GpuCommandBufferMsg_ConsoleMsg, OnConsoleMessage);
     IPC_MESSAGE_HANDLER(GpuCommandBufferMsg_SetMemoryAllocation,
                         OnSetMemoryAllocation);
@@ -75,13 +74,6 @@ void CommandBufferProxyImpl::OnDestroyed(gpu::error::ContextLostReason reason) {
   }
 }
 
-void CommandBufferProxyImpl::OnEchoAck() {
-  DCHECK(!echo_tasks_.empty());
-  base::Closure callback = echo_tasks_.front();
-  echo_tasks_.pop();
-  callback.Run();
-}
-
 void CommandBufferProxyImpl::OnConsoleMessage(
     const GPUCommandBufferConsoleMessage& message) {
   if (!console_message_callback_.is_null()) {
@@ -354,19 +346,6 @@ int CommandBufferProxyImpl::GetRouteID() const {
   return route_id_;
 }
 
-void CommandBufferProxyImpl::Echo(const base::Closure& callback) {
-  if (last_state_.error != gpu::error::kNoError) {
-    return;
-  }
-
-  if (!Send(new GpuCommandBufferMsg_Echo(
-           route_id_, GpuCommandBufferMsg_EchoAck(route_id_)))) {
-    return;
-  }
-
-  echo_tasks_.push(callback);
-}
-
 uint32 CommandBufferProxyImpl::CreateStreamTexture(uint32 texture_id) {
   if (last_state_.error != gpu::error::kNoError)
     return 0;