cc: Add MainAndImplFrameTimeDelta UMA.

cc/scheduler/scheduler_state_machine.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/scheduler/scheduler_state_machine.h"
 
 #include "base/format_macros.h"
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
 #include "base/trace_event/trace_event.h"
@@ skipping 595 matching lines @@
       output_surface_state_ = OUTPUT_SURFACE_ACTIVE;
     }
   }
 
   // Update state if there's no updates heading for the active tree, but we need
   // to do a forced draw.
   if (commit_has_no_updates &&
       forced_redraw_state_ == FORCED_REDRAW_STATE_WAITING_FOR_DRAW) {
     DCHECK(!has_pending_tree_);
     needs_redraw_ = true;
-    active_tree_needs_first_draw_ = true;
   }
 
   // This post-commit work is common to both completed and aborted commits.
   pending_tree_is_ready_for_activation_ = false;
 
   last_commit_had_no_updates_ = commit_has_no_updates;
 }
 
 void SchedulerStateMachine::WillActivate() {
   if (begin_main_frame_state_ ==
@@ skipping 516 matching lines @@
     case OUTPUT_SURFACE_ACTIVE:
     case OUTPUT_SURFACE_WAITING_FOR_FIRST_COMMIT:
     case OUTPUT_SURFACE_WAITING_FOR_FIRST_ACTIVATION:
       return true;
   }
   NOTREACHED();
   return false;
 }
 
 }  // namespace cc