Coalesce async touch move events until the ack back from render

content/browser/renderer_host/input/touch_event_queue_unittest.cc

 // Copyright 2013 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 "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "content/browser/renderer_host/input/timeout_monitor.h"
 #include "content/browser/renderer_host/input/touch_event_queue.h"
@@ skipping 100 matching lines @@
     WebGestureEvent event;
     event.type = type;
     queue_->OnGestureScrollEvent(
         GestureEventWithLatencyInfo(event, ui::LatencyInfo()));
   }
 
   void SendTouchEventAck(InputEventAckState ack_result) {
     queue_->ProcessTouchAck(ack_result, ui::LatencyInfo());
   }
 
+  void SendUncancelableTouchMoveEventAck() {
+    queue_->ProcessUncancelableTouchMoveAck();
+  }
+
   void SendGestureEventAck(WebInputEvent::Type type,
                            InputEventAckState ack_result) {
     blink::WebGestureEvent gesture_event;
     gesture_event.type = type;
     GestureEventWithLatencyInfo event(gesture_event, ui::LatencyInfo());
     queue_->OnGestureEventAck(event, ack_result);
   }
 
   void SetFollowupEvent(const WebTouchEvent& event) {
     followup_touch_event_.reset(new WebTouchEvent(event));
@@ skipping 133 matching lines @@
   InputEventAckState acked_event_state() const {
     return last_acked_event_state_;
   }
 
   static void RunTasksAndWait(base::TimeDelta delay) {
     base::MessageLoop::current()->PostDelayedTask(
         FROM_HERE, base::MessageLoop::QuitClosure(), delay);
     base::MessageLoop::current()->Run();
   }
 
+  int uncancelable_touch_moves_pending_ack_count() const {
+    return queue_->UncancelableTouchMovesPendingAckCount();
+  }
+
  private:
   void SendTouchEvent() {
     SendTouchEvent(touch_event_);
     touch_event_.ResetPoints();
   }
 
   void ResetQueueWithConfig(const TouchEventQueue::Config& config) {
     queue_.reset(new TouchEventQueue(this, config));
     queue_->OnHasTouchEventHandlers(true);
   }
@@ skipping 1343 matching lines @@
   followup_scroll.type = WebInputEvent::GestureScrollBegin;
   SetFollowupEvent(followup_scroll);
   SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_EQ(1U, GetAndResetSentEventCount());
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
 
   MoveTouchPoint(0, 0, 6);
   followup_scroll.type = WebInputEvent::GestureScrollUpdate;
   SetFollowupEvent(followup_scroll);
   SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  SendUncancelableTouchMoveEventAck();
   EXPECT_FALSE(HasPendingAsyncTouchMove());
   EXPECT_EQ(1U, GetAndResetSentEventCount());
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
 
   MoveTouchPoint(0, 0, 10);
   SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_TRUE(HasPendingAsyncTouchMove());
   EXPECT_EQ(0U, queued_event_count());
   EXPECT_EQ(0U, GetAndResetSentEventCount());
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
@@ skipping 13 matching lines @@
   EXPECT_FALSE(sent_event().cancelable);
   EXPECT_EQ(1U, queued_event_count());
   EXPECT_EQ(1U, GetAndResetSentEventCount());
   EXPECT_EQ(0U, GetAndResetAckedEventCount());
   SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_EQ(0U, queued_event_count());
   EXPECT_EQ(0U, GetAndResetSentEventCount());
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
 
   // Non-touchmove events should always flush any pending touchmove events.
-  MoveTouchPoint(0, 0, 25);
+  MoveTouchPoint(0, 10, 25);

[tdresser, 2015/03/27 13:34:44]

Why the change in location?

[lanwei, 2015/03/31 13:07:49]

Done.

   EXPECT_TRUE(HasPendingAsyncTouchMove());
   EXPECT_EQ(0U, queued_event_count());
   EXPECT_EQ(0U, GetAndResetSentEventCount());
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
   PressTouchPoint(30, 30);
   EXPECT_FALSE(HasPendingAsyncTouchMove());
   EXPECT_FALSE(sent_event().cancelable);
   EXPECT_EQ(WebInputEvent::TouchMove, sent_event().type);
   EXPECT_EQ(1U, GetAndResetSentEventCount());
   EXPECT_EQ(2U, queued_event_count());
@@ skipping 143 matching lines @@
   SendGestureEventAck(WebInputEvent::GestureScrollUpdate,
                       INPUT_EVENT_ACK_STATE_CONSUMED);
 
   // An async touch should fire after the throttling interval has expired, but
   // it should not start the touch ack timeout.
   MoveTouchPoint(0, 5, 5);
   EXPECT_TRUE(HasPendingAsyncTouchMove());
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
 
   AdvanceTouchTime(kMinSecondsBetweenThrottledTouchmoves + 0.1);
+  SendUncancelableTouchMoveEventAck();
   MoveTouchPoint(0, 5, 5);
   EXPECT_FALSE(IsTimeoutRunning());
   EXPECT_FALSE(HasPendingAsyncTouchMove());
   EXPECT_FALSE(sent_event().cancelable);
   SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
   EXPECT_EQ(1U, GetAndResetSentEventCount());
 
   // An unconsumed scroll event will resume synchronous touchmoves, which are
   // subject to the ack timeout.
@@ skipping 120 matching lines @@
   SendGestureEvent(WebInputEvent::GestureScrollEnd);
   ResetTouchEvent();
 
   PressTouchPoint(0, 0);
   EXPECT_EQ(1U, GetAndResetSentEventCount());
   EXPECT_EQ(WebInputEvent::TouchStart, sent_event().type);
   SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
 }
 
+// Ensure that even when the interval expires, we still need to wait for the
+// ack sent back from render to send the next async touchmove once the scroll
+// starts.
+TEST_F(TouchEventQueueTest, SendNextThrottledAsyncTouchMoveAfterAck) {
+  // Process a TouchStart
+  PressTouchPoint(0, 1);
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  // Initiate async touchmove dispatch after the start of a scroll sequence.
+  MoveTouchPoint(0, 0, 5);
+  WebGestureEvent followup_scroll;
+  followup_scroll.type = WebInputEvent::GestureScrollBegin;
+  SetFollowupEvent(followup_scroll);
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  MoveTouchPoint(0, 0, 10);
+  followup_scroll.type = WebInputEvent::GestureScrollUpdate;
+  SetFollowupEvent(followup_scroll);
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_FALSE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  // Now queue a second touchmove and verify it's not (yet) dispatched, because
+  // we've now started scrolling, and we throttle the touchmoves.
+  MoveTouchPoint(0, 0, 20);
+  EXPECT_TRUE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());

[tdresser, 2015/03/27 13:34:44]

Add a comment that this was a fake ack. It's probably worth clarifying this for
the first fake ack per test.

[lanwei, 2015/03/31 13:07:49]

Done.

+
+  // Coalesce the subsequent touchmove with pending_async_touch_move_ but don't
+  // dispatch it yet.
+  MoveTouchPoint(0, 0, 30);
+  EXPECT_TRUE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+  EXPECT_EQ(0, uncancelable_touch_moves_pending_ack_count());
+

[tdresser, 2015/03/27 13:34:44]

Add a comment describing what happens below.

[lanwei, 2015/03/31 13:07:49]

Done.

+  AdvanceTouchTime(kMinSecondsBetweenThrottledTouchmoves + 0.1);

[tdresser, 2015/03/27 13:34:44]

It might be clearer what's happening if we had a set of assertions between
advancing the time and moving the pointer.

[lanwei, 2015/03/31 13:07:49]

Done.

[lanwei, 2015/03/31 13:07:49]

Done.

+  MoveTouchPoint(0, 0, 40);
+  EXPECT_FALSE(HasPendingAsyncTouchMove());
+  EXPECT_FALSE(sent_event().cancelable);
+  EXPECT_EQ(1U, queued_event_count());
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(0U, GetAndResetAckedEventCount());
+  EXPECT_EQ(1, uncancelable_touch_moves_pending_ack_count());
+
+  // We receive the fake ack for touchmove and clear the queue.

[tdresser, 2015/03/27 13:34:44]

Which touchmove is this the fake ack for? The fake acks will always be
dispatched synchronously, so we won't be able to get:

TM1 - TM2 - sync ack for TM1

+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  // Do not dispatch the event until ThrottledTouchmoves intervals expires and
+  // receive an ack from render.
+  AdvanceTouchTime(kMinSecondsBetweenThrottledTouchmoves + 0.1);
+  MoveTouchPoint(0, 0, 50);
+  EXPECT_TRUE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+  EXPECT_EQ(1, uncancelable_touch_moves_pending_ack_count());
+
+  // Send pending_async_touch_move_ when we receive an ack back from render.
+  SendUncancelableTouchMoveEventAck();
+  EXPECT_FALSE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(1U, queued_event_count());
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(0U, GetAndResetAckedEventCount());
+  EXPECT_EQ(1, uncancelable_touch_moves_pending_ack_count());
+}
+
+// Ensure that even when we receive the ack from render, we still need to wait
+// for the interval expires to send the next async touchmove once the scroll
+// starts.
+TEST_F(TouchEventQueueTest, SendNextAsyncTouchMoveAfterAckAndTimeExpire) {
+  // Process a TouchStart
+  PressTouchPoint(0, 1);
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  // Initiate async touchmove dispatch after the start of a scroll sequence.
+  MoveTouchPoint(0, 0, 5);
+  WebGestureEvent followup_scroll;
+  followup_scroll.type = WebInputEvent::GestureScrollBegin;
+  SetFollowupEvent(followup_scroll);
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  MoveTouchPoint(0, 0, 10);
+  followup_scroll.type = WebInputEvent::GestureScrollUpdate;
+  SetFollowupEvent(followup_scroll);
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_FALSE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  // Now queue a second touchmove and verify it's not (yet) dispatched, because
+  // we've now started scrolling, and we throttle the touchmoves.
+  MoveTouchPoint(0, 0, 20);
+  EXPECT_TRUE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  // Coalesce the subsequent touchmove with pending_async_touch_move_ but don't
+  // dispatch it yet.
+  MoveTouchPoint(0, 0, 30);
+  EXPECT_TRUE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+  EXPECT_EQ(0, uncancelable_touch_moves_pending_ack_count());
+
+  AdvanceTouchTime(kMinSecondsBetweenThrottledTouchmoves + 0.1);
+  MoveTouchPoint(0, 0, 40);
+  EXPECT_FALSE(HasPendingAsyncTouchMove());
+  EXPECT_FALSE(sent_event().cancelable);
+  EXPECT_EQ(1U, queued_event_count());
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(0U, GetAndResetAckedEventCount());
+  EXPECT_EQ(1, uncancelable_touch_moves_pending_ack_count());
+
+  // We receive the fake ack for touchmove and clear the queue.
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  // We receive an ack back from render but the time interval is not expired,
+  // so we do not dispatch the event.
+  SendUncancelableTouchMoveEventAck();
+  EXPECT_EQ(0, uncancelable_touch_moves_pending_ack_count());
+
+  MoveTouchPoint(0, 0, 50);
+  EXPECT_TRUE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  AdvanceTouchTime(kMinSecondsBetweenThrottledTouchmoves + 0.1);
+  MoveTouchPoint(0, 0, 50);
+  EXPECT_FALSE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(WebInputEvent::TouchMove, sent_event().type);
+  EXPECT_FALSE(sent_event().cancelable);
+  EXPECT_EQ(1U, queued_event_count());
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(0U, GetAndResetAckedEventCount());
+  EXPECT_EQ(1, uncancelable_touch_moves_pending_ack_count());
+}
+
+TEST_F(TouchEventQueueTest, AsyncTouchFlushedByNonTouchMove) {
+  // Process a TouchStart
+  PressTouchPoint(0, 1);
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  // Initiate async touchmove dispatch after the start of a scroll sequence.
+  MoveTouchPoint(0, 0, 5);
+  WebGestureEvent followup_scroll;
+  followup_scroll.type = WebInputEvent::GestureScrollBegin;
+  SetFollowupEvent(followup_scroll);
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  MoveTouchPoint(0, 0, 10);
+  followup_scroll.type = WebInputEvent::GestureScrollUpdate;
+  SetFollowupEvent(followup_scroll);
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_FALSE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  // Now queue a second touchmove and verify it's not (yet) dispatched, because
+  // we've now started scrolling, and we throttle the touchmoves.
+  MoveTouchPoint(0, 0, 20);
+  EXPECT_TRUE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+  EXPECT_EQ(0, uncancelable_touch_moves_pending_ack_count());
+
+  AdvanceTouchTime(kMinSecondsBetweenThrottledTouchmoves + 0.1);
+  MoveTouchPoint(0, 0, 40);
+  EXPECT_FALSE(HasPendingAsyncTouchMove());
+  EXPECT_FALSE(sent_event().cancelable);
+  EXPECT_EQ(1U, queued_event_count());
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(0U, GetAndResetAckedEventCount());
+  EXPECT_EQ(1, uncancelable_touch_moves_pending_ack_count());
+
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+
+  for (int i = 0; i < 3; ++i) {
+    MoveTouchPoint(0, 10+10*i, 10+10*i);
+    EXPECT_TRUE(HasPendingAsyncTouchMove());
+    EXPECT_EQ(0U, queued_event_count());
+    EXPECT_EQ(0U, GetAndResetSentEventCount());
+    EXPECT_EQ(1U, GetAndResetAckedEventCount());
+    EXPECT_EQ(i+1, uncancelable_touch_moves_pending_ack_count());
+
+    // Send touchstart will flush pending_async_touch_move_, and increase the
+    // count.
+    PressTouchPoint(30, 30);
+    EXPECT_FALSE(HasPendingAsyncTouchMove());
+    EXPECT_EQ(WebInputEvent::TouchMove, sent_event().type);
+    EXPECT_FALSE(sent_event().cancelable);
+    EXPECT_EQ(10+10*i, sent_event().touches[0].position.x);
+    EXPECT_EQ(10+10*i, sent_event().touches[0].position.y);
+    EXPECT_EQ(1U, GetAndResetSentEventCount());
+    EXPECT_EQ(i+2, uncancelable_touch_moves_pending_ack_count());
+
+    // Touchstart is cancelable during async touch dispatch.
+    SendTouchEventAck(INPUT_EVENT_ACK_STATE_IGNORED);
+    EXPECT_EQ(WebInputEvent::TouchStart, sent_event().type);
+    EXPECT_TRUE(sent_event().cancelable);
+    EXPECT_EQ(1U, GetAndResetSentEventCount());
+    EXPECT_EQ(0U, GetAndResetAckedEventCount());
+    EXPECT_EQ(i+2, uncancelable_touch_moves_pending_ack_count());
+
+    SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+    EXPECT_EQ(0U, queued_event_count());
+    EXPECT_FALSE(HasPendingAsyncTouchMove());
+    EXPECT_EQ(0U, GetAndResetSentEventCount());
+    EXPECT_EQ(1U, GetAndResetAckedEventCount());
+  }
+
+  EXPECT_EQ(4, uncancelable_touch_moves_pending_ack_count());
+  // When we receive an ack from render we decrease the count.
+  SendUncancelableTouchMoveEventAck();
+  EXPECT_EQ(3, uncancelable_touch_moves_pending_ack_count());
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_FALSE(HasPendingAsyncTouchMove());
+
+  // Do not dispatch the next uncancelable touchmove when we have not recevied
+  // all the acks back from render.
+  AdvanceTouchTime(kMinSecondsBetweenThrottledTouchmoves + 0.1);
+  MoveTouchPoint(0, 20, 30);
+  EXPECT_TRUE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_EQ(0U, GetAndResetSentEventCount());
+  EXPECT_EQ(1U, GetAndResetAckedEventCount());
+  EXPECT_EQ(3, uncancelable_touch_moves_pending_ack_count());
+
+  // Once we receive the ack from render, we do not dispatch the
+  // pending_async_touchmove_ until the count is 0.
+  SendUncancelableTouchMoveEventAck();
+  EXPECT_EQ(2, uncancelable_touch_moves_pending_ack_count());
+  EXPECT_EQ(0U, queued_event_count());
+  EXPECT_TRUE(HasPendingAsyncTouchMove());
+
+  SendUncancelableTouchMoveEventAck();
+
+  // When we receive this ack from render, and the count is 0, so we can
+  // dispatch the pending_async_touchmove_.
+  SendUncancelableTouchMoveEventAck();
+  EXPECT_EQ(1, uncancelable_touch_moves_pending_ack_count());
+  EXPECT_FALSE(HasPendingAsyncTouchMove());
+  EXPECT_EQ(1U, queued_event_count());
+  EXPECT_EQ(WebInputEvent::TouchMove, sent_event().type);
+  EXPECT_FALSE(sent_event().cancelable);
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+  EXPECT_EQ(0U, GetAndResetAckedEventCount());
+}
+
 TEST_F(TouchEventQueueTest, TouchAbsorptionWithConsumedFirstMove) {
   // Queue a TouchStart.
   PressTouchPoint(0, 1);
   SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_EQ(0U, queued_event_count());
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
 
   MoveTouchPoint(0, 20, 5);
   SendGestureEvent(blink::WebInputEvent::GestureScrollBegin);
   SendTouchEventAck(INPUT_EVENT_ACK_STATE_CONSUMED);
@@ skipping 68 matching lines @@
 
   // If subsequent touchmoves aren't consumed, the generated scroll events
   // will restore async touch dispatch.
   MoveTouchPoint(0, 25, 5);
   SendTouchEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   SendGestureEvent(blink::WebInputEvent::GestureScrollUpdate);
   ASSERT_EQ(1U, GetAndResetSentEventCount());
   EXPECT_TRUE(sent_event().cancelable);
   AdvanceTouchTime(kMinSecondsBetweenThrottledTouchmoves + 0.1);
   MoveTouchPoint(0, 30, 5);
+  SendUncancelableTouchMoveEventAck();
   ASSERT_EQ(1U, GetAndResetSentEventCount());
   SendTouchEventAck(INPUT_EVENT_ACK_STATE_IGNORED);
   EXPECT_FALSE(sent_event().cancelable);
 
   // The touchend will be uncancelable during an active scroll sequence.
   ReleaseTouchPoint(0);
   ASSERT_EQ(1U, GetAndResetSentEventCount());
   EXPECT_FALSE(sent_event().cancelable);
 }
 
@@ skipping 180 matching lines @@
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
 
   // TouchMove should be allowed and test for touches state.
   const WebTouchEvent& event2 = sent_event();
   EXPECT_EQ(WebInputEvent::TouchMove, event2.type);
   EXPECT_EQ(WebTouchPoint::StateStationary, event2.touches[0].state);
   EXPECT_EQ(WebTouchPoint::StateMoved, event2.touches[1].state);
 }
 
 }  // namespace content