ui: Add debug flag for slowing down all UI animations.

ui/compositor/compositor.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 "ui/compositor/compositor.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <deque>
@@ skipping 21 matching lines @@
 #include "cc/surfaces/surface_manager.h"
 #include "cc/trees/layer_tree_host_in_process.h"
 #include "cc/trees/layer_tree_settings.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/compositor/compositor_observer.h"
 #include "ui/compositor/compositor_switches.h"
 #include "ui/compositor/compositor_vsync_manager.h"
 #include "ui/compositor/dip_util.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_animator_collection.h"
+#include "ui/compositor/scoped_animation_duration_scale_mode.h"
 #include "ui/gl/gl_switches.h"
 
 namespace {
 
 const double kDefaultRefreshRate = 60.0;
 const double kTestRefreshRate = 200.0;
 
 // TODO(mfomitchev, fsamuel): Look at removing this when transition from
 // SurfaceSequence to SurfaceReference is fully complete.
 // Used when ui::Compositor is created with null ContextFactoryPrivate.
@@ skipping 159 matching lines @@
   UMA_HISTOGRAM_TIMES("GPU.CreateBrowserCompositor",
                       base::TimeTicks::Now() - before_create);
 
   animation_timeline_ =
       cc::AnimationTimeline::Create(cc::AnimationIdProvider::NextTimelineId());
   animation_host_->AddAnimationTimeline(animation_timeline_.get());
 
   host_->GetLayerTree()->SetRootLayer(root_web_layer_);
   host_->SetFrameSinkId(frame_sink_id_);
   host_->SetVisible(true);
+
+  if (command_line->HasSwitch(switches::kUISlowAnimations)) {
+    slow_animations_.reset(new ScopedAnimationDurationScaleMode(

[danakj, 2017/01/09 15:39:31]

use base::MakeUnique instead of new

[reveman, 2017/01/09 22:27:49]

Done.

+        ScopedAnimationDurationScaleMode::SLOW_DURATION));
+  }
 }
 
 Compositor::~Compositor() {
   TRACE_EVENT0("shutdown", "Compositor::destructor");
 
   CancelCompositorLock();
   DCHECK(!compositor_lock_);
 
   for (auto& observer : observer_list_)
     observer.OnCompositingShuttingDown(this);
@@ skipping 333 matching lines @@
   for (auto& observer : observer_list_)
     observer.OnCompositingLockStateChanged(this);
 }
 
 void Compositor::CancelCompositorLock() {
   if (compositor_lock_)
     compositor_lock_->CancelLock();
 }
 
 }  // namespace ui