cc: Removing base::TimeTicks argument to DrawLayers as it isn't used.

cc/trees/layer_tree_host_impl.cc

 // Copyright 2011 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 "cc/trees/layer_tree_host_impl.h"
 
 #include <algorithm>
 #include <limits>
 #include <map>
 #include <set>
@@ skipping 1439 matching lines @@
   if (!InnerViewportScrollLayer())
     return metadata;
 
   // TODO(miletus) : Change the metadata to hold ScrollOffset.
   metadata.root_scroll_offset = gfx::ScrollOffsetToVector2dF(
       active_tree_->TotalScrollOffset());
 
   return metadata;
 }
 
-void LayerTreeHostImpl::DrawLayers(FrameData* frame,
-                                   base::TimeTicks frame_begin_time) {
+void LayerTreeHostImpl::DrawLayers(FrameData* frame) {
   TRACE_EVENT0("cc", "LayerTreeHostImpl::DrawLayers");
+
+  base::TimeTicks frame_begin_time = CurrentBeginFrameArgs().frame_time;

[danakj, 2015/04/24 17:24:22]

I think I prefer passing things to a function rather than pulling them out of
some state on the class when it's not troublesome to do so.

[danakj, 2015/04/24 17:24:46]

(Esp for such a complicated/huge class as this)

   DCHECK(CanDraw());
 
   if (!frame->composite_events.empty()) {
     frame_timing_tracker_->SaveTimeStamps(frame_begin_time,
                                           frame->composite_events);
   }
 
   if (frame->has_no_damage) {
     TRACE_EVENT_INSTANT0("cc", "EarlyOut_NoDamage", TRACE_EVENT_SCOPE_THREAD);
     DCHECK(!output_surface_->capabilities()
@@ skipping 1893 matching lines @@
   new_target.SetToMin(layer_impl->MaxScrollOffset());
 
   curve->UpdateTarget(
       animation->TrimTimeToCurrentIteration(CurrentBeginFrameArgs().frame_time)
           .InSecondsF(),
       new_target);
 
   return true;
 }
 }  // namespace cc