[cc] Don't send missed BeginFrames with past deadline.

cc/scheduler/begin_frame_source.cc

Index: cc/scheduler/begin_frame_source.cc
diff --git a/cc/scheduler/begin_frame_source.cc b/cc/scheduler/begin_frame_source.cc
index 714f505037b230186cd85245f8f87f9b1b372ad9..f2076e4b5457722af841cc248aef770d60fa6b66 100644
--- a/cc/scheduler/begin_frame_source.cc
+++ b/cc/scheduler/begin_frame_source.cc
@@ -364,7 +364,11 @@ void ExternalBeginFrameSource::AddObserver(BeginFrameObserver* obs) {
               last_args.sequence_number))
           << "current " << missed_begin_frame_args_.AsValue()->ToString()
           << ", last " << last_args.AsValue()->ToString();
-      obs->OnBeginFrame(missed_begin_frame_args_);
+      // Avoid issuing missed BeginFrames with a past deadline.
+      if (missed_begin_frame_args_.deadline.is_null() ||
+          missed_begin_frame_args_.deadline > Now()) {
+        obs->OnBeginFrame(missed_begin_frame_args_);
+      }
     }
   }
 }
@@ -442,4 +446,8 @@ void ExternalBeginFrameSource::FinishFrame() {
   client_->OnDidFinishFrame(ack);
 }
 
+base::TimeTicks ExternalBeginFrameSource::Now() const {
+  return base::TimeTicks::Now();
+}
+
 }  // namespace cc