Report user actions when gesture starts and stops in user_model.

content/renderer/render_thread_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.
 
 #include "content/renderer/render_thread_impl.h"
 
 #include <algorithm>
 #include <limits>
 #include <map>
 #include <utility>
@@ skipping 616 matching lines @@
                           .Build()),
       renderer_scheduler_(std::move(scheduler)),
       main_message_loop_(std::move(main_message_loop)),
       raster_worker_pool_(new RasterWorkerPool()) {
   Init();
 }
 
 void RenderThreadImpl::Init() {
   TRACE_EVENT0("startup", "RenderThreadImpl::Init");
 
+  base::RemoveActionCallback(action_callback_);

[Ilya Sherman, 2016/03/21 08:09:44]

Hmm, why is this line needed?

[beaudoin, 2016/03/23 02:46:42]

Copied the pattern from components/metrics/metrics_service.cc

Suggest leaving it as-is for now.

[Ilya Sherman, 2016/03/24 05:02:35]

The example you gave is not an init function -- it's a method that can be called
multiple times.  It's still a little suspect there, but I'm almost completely
certain that you don't need this line here... and I find the line pretty
confusing to read here.

[beaudoin, 2016/03/24 21:08:55]

It's gone now. :)

+  action_callback_ = base::Bind(&RenderThreadImpl::RecordComputedAction,
+                                base::Unretained(this));
+  base::AddActionCallback(action_callback_);
+
   base::trace_event::TraceLog::GetInstance()->SetThreadSortIndex(
       base::PlatformThread::CurrentId(),
       kTraceEventRendererMainThreadSortIndex);
 
 #if defined(OS_MACOSX) || (defined(OS_ANDROID) && !defined(USE_AURA))
   // On Mac and Android Java UI, the select popups are rendered by the browser.
   blink::WebView::setUseExternalPopupMenus(true);
 #endif
 
   lazy_tls.Pointer()->Set(this);
@@ skipping 199 matching lines @@
       base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kUseMusInRenderer))
     CreateRenderWidgetWindowTreeClientFactory();
 #endif
 
   service_registry()->ConnectToRemoteService(
       mojo::GetProxy(&storage_partition_service_));
 }
 
 RenderThreadImpl::~RenderThreadImpl() {
+  base::RemoveActionCallback(action_callback_);
 }
 
 void RenderThreadImpl::Shutdown() {
   FOR_EACH_OBSERVER(
       RenderProcessObserver, observers_, OnRenderProcessShutdown());
 
   if (memory_observer_) {
     message_loop()->RemoveTaskObserver(memory_observer_.get());
     memory_observer_.reset();
   }
@@ skipping 1309 matching lines @@
 }
 
 void RenderThreadImpl::PendingRenderFrameConnect::OnConnectionError() {
   size_t erased =
       RenderThreadImpl::current()->pending_render_frame_connects_.erase(
           routing_id_);
   DCHECK_EQ(1u, erased);
 }
 
 }  // namespace content