cc: Always use SetNeedsBeginFrame to request the next BeginFrame

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/values.h"
@@ skipping 751 matching lines @@
   // If the pending tree activates quickly, we'll want a BeginFrame soon
   // to draw the new active tree.
   if (has_pending_tree_)
     return true;
 
   // Changing priorities may allow us to activate (given the new priorities),
   // which may result in a new frame.
   if (needs_manage_tiles_)
     return true;
 
+  // If we just swapped, it's likely that we are going to produce another
+  // frame soon. This helps avoid negative glitches in our SetNeedsBeginFrame
+  // requests, which may propagate to the BeginFrame provider and get sampled
+  // at an inopportune time, delaying the next BeginFrame.
+  if (last_frame_number_swap_performed_ == current_frame_number_)
+    return true;
+
   return false;
 }
 
 void SchedulerStateMachine::DidEnterBeginFrame(const BeginFrameArgs& args) {
   current_frame_number_++;
   inside_begin_frame_ = true;
   last_begin_frame_args_ = args;
 }
 
 void SchedulerStateMachine::DidLeaveBeginFrame() {
@@ skipping 117 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