Report user actions when gesture starts and stops in user_model.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index 473d5a0de827c69b4a995ed80d93f2887dcddb32..6b3a24d12903a181c7b1570c085d94ca308b4ee1 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -21,6 +21,7 @@
 #include "base/memory/shared_memory.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
+#include "base/metrics/user_metrics.h"
 #include "base/path_service.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string16.h"
@@ -635,6 +636,9 @@ RenderThreadImpl::RenderThreadImpl(
 void RenderThreadImpl::Init() {
   TRACE_EVENT0("startup", "RenderThreadImpl::Init");
 
+  base::AddActionCallback(base::Bind(&RenderThreadImpl::RecordComputedAction,
+                                     base::Unretained(this)));

[Ilya Sherman, 2016/02/09 22:03:25]

Should the callback be removed in the destructor or something?

[beaudoin, 2016/02/11 22:03:28]

Done.

+
   base::trace_event::TraceLog::GetInstance()->SetThreadSortIndex(
       base::PlatformThread::CurrentId(),
       kTraceEventRendererMainThreadSortIndex);