Adding UMA for sync IPCs

content/browser/renderer_host/render_process_host_impl.cc

 // Copyright (c) 2012 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.
 
 // Represents the browser side of the browser <--> renderer communication
 // channel. There will be one RenderProcessHost per renderer process.
 
 #include "content/browser/renderer_host/render_process_host_impl.h"
 
 #if defined(OS_WIN)
@@ skipping 884 matching lines @@
     bool msg_is_ok = true;
     IPC_BEGIN_MESSAGE_MAP_EX(RenderProcessHostImpl, msg, msg_is_ok)
       IPC_MESSAGE_HANDLER(ChildProcessHostMsg_ShutdownRequest,
                           OnShutdownRequest)
       IPC_MESSAGE_HANDLER(ChildProcessHostMsg_DumpHandlesDone,
                           OnDumpHandlesDone)
       IPC_MESSAGE_HANDLER(ViewHostMsg_SuddenTerminationChanged,
                           SuddenTerminationChanged)
       IPC_MESSAGE_HANDLER(ViewHostMsg_UserMetricsRecordAction,
                           OnUserMetricsRecordAction)
+      IPC_MESSAGE_HANDLER(ViewHostMsg_SyncIPCElapsedTime,
+                          OnSyncIPCElapsedTime)
       IPC_MESSAGE_HANDLER(ViewHostMsg_SavedPageAsMHTML, OnSavedPageAsMHTML)
       // Adding single handlers for your service here is fine, but once your
       // service needs more than one handler, please extract them into a new
       // message filter and add that filter to CreateMessageFilters().
       IPC_MESSAGE_UNHANDLED_ERROR()
     IPC_END_MESSAGE_MAP_EX()
 
     if (!msg_is_ok) {
       // The message had a handler, but its de-serialization failed.
       // We consider this a capital crime. Kill the renderer if we have one.
@@ skipping 444 matching lines @@
     Send(queued_messages_.front());
     queued_messages_.pop();
   }
 }
 
 void RenderProcessHostImpl::OnUserMetricsRecordAction(
     const std::string& action) {
   content::RecordComputedAction(action);
 }
 
+void RenderProcessHostImpl::OnSyncIPCElapsedTime(const base::TimeDelta& delta) {
+  HISTOGRAM_TIMES("RendererSyncIPC.ElapsedTime", delta);
+}
+
 void RenderProcessHostImpl::OnSavedPageAsMHTML(int job_id, int64 data_size) {
   MHTMLGenerationManager::GetInstance()->MHTMLGenerated(job_id, data_size);
 }
 
 void RenderProcessHostImpl::OnCompositorSurfaceBuffersSwappedNoHost(
       int32 surface_id,
       uint64 surface_handle,
       int32 route_id,
       int32 gpu_process_host_id) {
   TRACE_EVENT0("renderer_host",
                "RenderWidgetHostImpl::OnCompositorSurfaceBuffersSwappedNoHost");
   RenderWidgetHostImpl::AcknowledgeSwapBuffers(route_id,
                                                gpu_process_host_id);
 }