cc: Change texture locking check point

cc/scheduler/scheduler_state_machine.cc

Index: cc/scheduler/scheduler_state_machine.cc
diff --git a/cc/scheduler/scheduler_state_machine.cc b/cc/scheduler/scheduler_state_machine.cc
index 1111ba36f13c0030b50d5eb5373e563ce955815f..ba049285e79ada8762f35654957592fd5298adb5 100644
--- a/cc/scheduler/scheduler_state_machine.cc
+++ b/cc/scheduler/scheduler_state_machine.cc
@@ -303,6 +303,11 @@ bool SchedulerStateMachine::PendingDrawsShouldBeAborted() const {
   if (PendingActivationsShouldBeForced())
     return true;
 
+  // Impl thread should not draw anymore when texture is acquired by main thread
+  // because texture is controlled under main thread.
+  if (texture_state_ == LAYER_TEXTURE_STATE_ACQUIRED_BY_MAIN_THREAD)
+    return true;
+
   // Additional states where we should abort draws.
   // Note: We don't force activation in these cases because doing so would
   // result in checkerboarding on resize, becoming visible, etc.
@@ -317,11 +322,6 @@ bool SchedulerStateMachine::PendingActivationsShouldBeForced() const {
   // These are all the cases where, if we do not force activations to make
   // forward progress, we might deadlock with the main thread.
 
-  // The impl thread cannot lock layer textures unless the pending
-  // tree can be activated to unblock the commit.
-  if (texture_state_ == LAYER_TEXTURE_STATE_ACQUIRED_BY_MAIN_THREAD)
-    return true;
-
   // There is no output surface to trigger our activations.
   if (output_surface_state_ == OUTPUT_SURFACE_LOST)
     return true;
@@ -561,6 +561,10 @@ void SchedulerStateMachine::CheckInvariants() {
   // timeout simultaneously.
   DCHECK(!(forced_redraw_state_ == FORCED_REDRAW_STATE_WAITING_FOR_DRAW &&
            readback_state_ == READBACK_STATE_WAITING_FOR_DRAW_AND_READBACK));
+  // Main thread should never have the texture locked when there is a pending

[brianderson, 2014/03/06 17:56:25]

nit: line break above comment.

[simonhong, 2014/03/06 21:04:48]

Done.

+  // tree.
+  if (has_pending_tree_)

[brianderson, 2014/03/06 17:56:25]

Can you change this to:
if (has_pending_tree_ || active_tree_needs_first_draw_)

The impl thread shouldn't give up it's lock until after the commit has been
drawn for the first time.

[simonhong, 2014/03/06 21:04:48]

Done.

+    DCHECK(texture_state_ != LAYER_TEXTURE_STATE_ACQUIRED_BY_MAIN_THREAD);
 }
 
 void SchedulerStateMachine::UpdateState(Action action) {