Adjust cancelabilty of touchmoves that are queued when scroll start occurs

content/renderer/input/main_thread_event_queue_unittest.cc

Index: content/renderer/input/main_thread_event_queue_unittest.cc
diff --git a/content/renderer/input/main_thread_event_queue_unittest.cc b/content/renderer/input/main_thread_event_queue_unittest.cc
index 1760b26eed28b5aba1b927db28b25cf6ba36fe89..586660d561a005e812f36af91378663149d00f61 100644
--- a/content/renderer/input/main_thread_event_queue_unittest.cc
+++ b/content/renderer/input/main_thread_event_queue_unittest.cc
@@ -1033,4 +1033,38 @@ TEST_P(MainThreadEventQueueTest, QueuingClosuresBetweenEvents) {
             handled_tasks_.at(3)->taskAsEvent()->event().type());
 }
 
+TEST_P(MainThreadEventQueueTest, BlockingTouchMoveBecomesNonBlocking) {
+  SyntheticWebTouchEvent kEvents[2];
+  kEvents[0].PressPoint(10, 10);
+  kEvents[0].MovePoint(0, 20, 20);
+  kEvents[1].PressPoint(10, 10);
+  kEvents[1].ReleasePoint(0);
+  WebTouchEvent scroll_start(WebInputEvent::TouchScrollStarted,
+                             WebInputEvent::NoModifiers,
+                             WebInputEvent::TimeStampForTesting);
+
+  EXPECT_FALSE(main_task_runner_->HasPendingTask());
+  EXPECT_EQ(0u, event_queue().size());
+
+  EXPECT_EQ(WebInputEvent::Blocking, kEvents[0].dispatchType);
+  EXPECT_EQ(WebInputEvent::Blocking, kEvents[1].dispatchType);
+  EXPECT_FALSE(HandleEvent(kEvents[0], INPUT_EVENT_ACK_STATE_NOT_CONSUMED));
+  EXPECT_FALSE(HandleEvent(kEvents[1], INPUT_EVENT_ACK_STATE_NOT_CONSUMED));
+  EXPECT_FALSE(HandleEvent(scroll_start, INPUT_EVENT_ACK_STATE_NOT_CONSUMED));
+  EXPECT_EQ(3u, event_queue().size());
+  RunPendingTasksWithSimulatedRaf();
+  EXPECT_EQ(0u, event_queue().size());
+  EXPECT_FALSE(main_task_runner_->HasPendingTask());
+  EXPECT_FALSE(needs_main_frame_);
+
+  EXPECT_EQ(WebInputEvent::EventNonBlocking,
+            static_cast<const WebTouchEvent&>(
+                handled_tasks_.at(0)->taskAsEvent()->event())
+                .dispatchType);
+  EXPECT_EQ(WebInputEvent::Blocking,
+            static_cast<const WebTouchEvent&>(
+                handled_tasks_.at(1)->taskAsEvent()->event())
+                .dispatchType);
+}
+
 }  // namespace content