Coalesce async touch move events until the ack back from render

content/browser/renderer_host/render_widget_host_view_aura_unittest.cc

 // Copyright (c) 2012 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 "content/browser/renderer_host/render_widget_host_view_aura.h"
 
 #include "base/basictypes.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_vector.h"
 #include "base/memory/shared_memory.h"
@@ skipping 427 matching lines @@
     // which uses ObserverListThreadSafe, which furthermore remembers the
     // message loop for the thread it was created in. Between tests, the
     // RendererFrameManager singleton survives and and the MessageLoop gets
     // destroyed. The correct fix would be to have ObserverListThreadSafe look
     // up the proper message loop every time (see crbug.com/443824.)
     RendererFrameManager::GetInstance()->OnMemoryPressure(level);
   }
 
   void SendInputEventACK(WebInputEvent::Type type,
       InputEventAckState ack_result) {
-    InputHostMsg_HandleInputEvent_ACK_Params ack;
-    ack.type = type;
-    ack.state = ack_result;
+    DCHECK(!WebInputEvent::isTouchEventType(type));
+    InputEventAck ack(type, ack_result);
     InputHostMsg_HandleInputEvent_ACK response(0, ack);
     widget_host_->OnMessageReceived(response);
   }
+
+  void SendTouchEventACK(WebInputEvent::Type type,
+                         InputEventAckState ack_result,
+                         uint32 event_id) {
+    DCHECK(WebInputEvent::isTouchEventType(type));
+    InputEventAck ack(type, ack_result, event_id);
+    InputHostMsg_HandleInputEvent_ACK response(0, ack);
+    widget_host_->OnMessageReceived(response);
+  }
 
   size_t GetSentMessageCountAndResetSink() {
     size_t count = sink_->message_count();
     sink_->ClearMessages();
     return count;
   }
 
-  void AckLastSentInputEventIfNecessary(InputEventAckState ack_result) {
+  void AckLastSentInputEventIfNecessary(InputEventAckState ack_result,
+                                        uint32 event_id) {
     if (!sink_->message_count())
       return;
 
     InputMsg_HandleInputEvent::Param params;
     if (!InputMsg_HandleInputEvent::Read(
             sink_->GetMessageAt(sink_->message_count() - 1), &params)) {
       return;
     }
 
-    if (WebInputEventTraits::IgnoresAckDisposition(*get<0>(params)))
+    if (!WebInputEventTraits::WillReceiveAckFromRenderer(*get<0>(params)))
       return;
 
-    SendInputEventACK(get<0>(params)->type, ack_result);
+    SendTouchEventACK(get<0>(params)->type, ack_result, event_id);

[jdduke (slow), 2015/05/14 21:00:06]

Since we're already extracting the event from the IPC here, you could probably
just do:

const blink::WebInputEvent* event = get<0>(params);
SendTouchEventAck(event->type, ack_result,
WebInputEventTraits::GetUniqueTouchEventId(*event));

then you don't need the additional argument for this specific ack method. I
didn't realize this method was used by most of the touch-related acks.

   }
 
  protected:
   // If true, then calls RWH::Shutdown() instead of deleting RWH.
   bool widget_host_uses_shutdown_to_destroy_;
 
   bool is_guest_view_hack_;
 
   base::MessageLoopForUI message_loop_;
   BrowserThreadImpl browser_thread_for_ui_;
@@ skipping 206 matching lines @@
   }
 
   float overscroll_delta_y() const {
     return view_->overscroll_controller()->overscroll_delta_y_;
   }
 
   TestOverscrollDelegate* overscroll_delegate() {
     return overscroll_delegate_.get();
   }
 
-  void SendTouchEvent() {
+  uint32 SendTouchEvent() {
+    uint32 touch_event_id = touch_event_.uniqueTouchEventId;
     widget_host_->ForwardTouchEventWithLatencyInfo(touch_event_,
                                                    ui::LatencyInfo());
     touch_event_.ResetPoints();
+    return touch_event_id;
   }
 
   void PressTouchPoint(int x, int y) {
     touch_event_.PressPoint(x, y);
-    SendTouchEvent();
   }
 
   void MoveTouchPoint(int index, int x, int y) {
     touch_event_.MovePoint(index, x, y);
-    SendTouchEvent();
   }
 
   void ReleaseTouchPoint(int index) {
     touch_event_.ReleasePoint(index);
-    SendTouchEvent();
   }
 
   SyntheticWebTouchEvent touch_event_;
 
   scoped_ptr<TestOverscrollDelegate> overscroll_delegate_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAuraOverscrollTest);
 };
 
@@ skipping 367 matching lines @@
   view_->OnTouchEvent(&press);
   EXPECT_TRUE(press.synchronous_handling_disabled());
   EXPECT_EQ(blink::WebInputEvent::TouchStart, view_->touch_event_->type);
   EXPECT_EQ(1U, view_->touch_event_->touchesLength);
   EXPECT_EQ(blink::WebTouchPoint::StatePressed,
             view_->touch_event_->touches[0].state);
 
   widget_host_->OnMessageReceived(ViewHostMsg_HasTouchEventHandlers(0, false));
 
   // Ack'ing the outstanding event should flush the pending touch queue.
-  InputHostMsg_HandleInputEvent_ACK_Params ack;
-  ack.type = blink::WebInputEvent::TouchStart;
-  ack.state = INPUT_EVENT_ACK_STATE_NO_CONSUMER_EXISTS;
+  InputEventAck ack(blink::WebInputEvent::TouchStart,
+                    INPUT_EVENT_ACK_STATE_NO_CONSUMER_EXISTS,
+                    press.unique_event_id());
   widget_host_->OnMessageReceived(InputHostMsg_HandleInputEvent_ACK(0, ack));
   EXPECT_EQ(0U, GetSentMessageCountAndResetSink());
 
   ui::TouchEvent move2(ui::ET_TOUCH_MOVED, gfx::Point(20, 20), 0,
       base::Time::NowFromSystemTime() - base::Time());
   view_->OnTouchEvent(&move2);
   EXPECT_TRUE(press.synchronous_handling_disabled());
   EXPECT_EQ(blink::WebInputEvent::TouchMove, view_->touch_event_->type);
   EXPECT_EQ(1U, view_->touch_event_->touchesLength);
   EXPECT_EQ(blink::WebTouchPoint::StateMoved,
@@ skipping 11 matching lines @@
 TEST_F(RenderWidgetHostViewAuraTest, MultiTouchPointsStates) {
   view_->InitAsFullscreen(parent_view_);
   view_->Show();
   view_->UseFakeDispatcher();
   GetSentMessageCountAndResetSink();
 
   ui::TouchEvent press0(ui::ET_TOUCH_PRESSED, gfx::Point(30, 30), 0,
                         ui::EventTimeForNow());
 
   view_->OnTouchEvent(&press0);
-  SendInputEventACK(blink::WebInputEvent::TouchStart,
-                    INPUT_EVENT_ACK_STATE_CONSUMED);
+  SendTouchEventACK(blink::WebInputEvent::TouchStart,
+                    INPUT_EVENT_ACK_STATE_CONSUMED,
+                    press0.unique_event_id());
   EXPECT_EQ(blink::WebInputEvent::TouchStart, view_->touch_event_->type);
   EXPECT_EQ(1U, view_->touch_event_->touchesLength);
   EXPECT_EQ(1U, view_->dispatcher_->GetAndResetProcessedTouchEventCount());
 
   ui::TouchEvent move0(ui::ET_TOUCH_MOVED, gfx::Point(20, 20), 0,
                        ui::EventTimeForNow());
 
   view_->OnTouchEvent(&move0);
-  SendInputEventACK(blink::WebInputEvent::TouchMove,
-                    INPUT_EVENT_ACK_STATE_CONSUMED);
+  SendTouchEventACK(blink::WebInputEvent::TouchMove,
+                    INPUT_EVENT_ACK_STATE_CONSUMED,
+                    move0.unique_event_id());
   EXPECT_EQ(blink::WebInputEvent::TouchMove, view_->touch_event_->type);
   EXPECT_EQ(1U, view_->touch_event_->touchesLength);
   EXPECT_EQ(1U, view_->dispatcher_->GetAndResetProcessedTouchEventCount());
 
   // For the second touchstart, only the state of the second touch point is
   // StatePressed, the state of the first touch point is StateStationary.
   ui::TouchEvent press1(ui::ET_TOUCH_PRESSED, gfx::Point(10, 10), 1,
                         ui::EventTimeForNow());
 
   view_->OnTouchEvent(&press1);
-  SendInputEventACK(blink::WebInputEvent::TouchStart,
-                    INPUT_EVENT_ACK_STATE_CONSUMED);
+  SendTouchEventACK(blink::WebInputEvent::TouchStart,
+                    INPUT_EVENT_ACK_STATE_CONSUMED,
+                    press1.unique_event_id());
   EXPECT_EQ(blink::WebInputEvent::TouchStart, view_->touch_event_->type);
   EXPECT_EQ(2U, view_->touch_event_->touchesLength);
   EXPECT_EQ(1U, view_->dispatcher_->GetAndResetProcessedTouchEventCount());
 
   // For the touchmove of second point, the state of the second touch point is
   // StateMoved, the state of the first touch point is StateStationary.
   ui::TouchEvent move1(ui::ET_TOUCH_MOVED, gfx::Point(30, 30), 1,
                        ui::EventTimeForNow());
 
   view_->OnTouchEvent(&move1);
-  SendInputEventACK(blink::WebInputEvent::TouchMove,
-                    INPUT_EVENT_ACK_STATE_CONSUMED);
+  SendTouchEventACK(blink::WebInputEvent::TouchMove,
+                    INPUT_EVENT_ACK_STATE_CONSUMED,
+                    move1.unique_event_id());
   EXPECT_EQ(blink::WebInputEvent::TouchMove, view_->touch_event_->type);
   EXPECT_EQ(2U, view_->touch_event_->touchesLength);
   EXPECT_EQ(1U, view_->dispatcher_->GetAndResetProcessedTouchEventCount());
 
   // For the touchmove of first point, the state of the first touch point is
   // StateMoved, the state of the second touch point is StateStationary.
   ui::TouchEvent move2(ui::ET_TOUCH_MOVED, gfx::Point(10, 10), 0,
                        ui::EventTimeForNow());
 
   view_->OnTouchEvent(&move2);
-  SendInputEventACK(blink::WebInputEvent::TouchMove,
-                    INPUT_EVENT_ACK_STATE_CONSUMED);
+  SendTouchEventACK(blink::WebInputEvent::TouchMove,
+                    INPUT_EVENT_ACK_STATE_CONSUMED,
+                    move2.unique_event_id());
   EXPECT_EQ(blink::WebInputEvent::TouchMove, view_->touch_event_->type);
   EXPECT_EQ(2U, view_->touch_event_->touchesLength);
   EXPECT_EQ(1U, view_->dispatcher_->GetAndResetProcessedTouchEventCount());
 
   ui::TouchEvent cancel0(ui::ET_TOUCH_CANCELLED, gfx::Point(10, 10), 0,
                          ui::EventTimeForNow());
 
   // For the touchcancel, only the state of the current touch point is
   // StateCancelled, the state of the other touch point is StateStationary.
   view_->OnTouchEvent(&cancel0);
@@ skipping 1658 matching lines @@
 
 // Tests that when touch-events are dispatched to the renderer, the overscroll
 // gesture deals with them correctly.
 TEST_F(RenderWidgetHostViewAuraOverscrollTest, OverscrollWithTouchEvents) {
   SetUpOverscrollEnvironmentWithDebounce(10);
   widget_host_->OnMessageReceived(ViewHostMsg_HasTouchEventHandlers(0, true));
   sink_->ClearMessages();
 
   // The test sends an intermingled sequence of touch and gesture events.
   PressTouchPoint(0, 1);
-  SendInputEventACK(WebInputEvent::TouchStart,
-                    INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  uint32 touch_press_event_id1 = SendTouchEvent();
+  SendTouchEventACK(WebInputEvent::TouchStart,
+                    INPUT_EVENT_ACK_STATE_NOT_CONSUMED, touch_press_event_id1);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
 
   MoveTouchPoint(0, 20, 5);
+  uint32 touch_move_event_id1 = SendTouchEvent();
+  SendTouchEventACK(WebInputEvent::TouchMove,
+                    INPUT_EVENT_ACK_STATE_NOT_CONSUMED, touch_move_event_id1);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
-  SendInputEventACK(WebInputEvent::TouchMove,
-                    INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
 
   EXPECT_EQ(OVERSCROLL_NONE, overscroll_mode());
   EXPECT_EQ(OVERSCROLL_NONE, overscroll_delegate()->current_mode());
 
   SimulateGestureEvent(WebInputEvent::GestureScrollBegin,
                        blink::WebGestureDeviceTouchscreen);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
   SimulateGestureScrollUpdateEvent(20, 0, 0);
   SendInputEventACK(WebInputEvent::GestureScrollUpdate,
                     INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
   EXPECT_EQ(OVERSCROLL_NONE, overscroll_mode());
   EXPECT_EQ(OVERSCROLL_NONE, overscroll_delegate()->current_mode());
 
   // Another touch move event should reach the renderer since overscroll hasn't
   // started yet.  Note that touch events sent during the scroll period may
   // not require an ack (having been marked uncancelable).
   MoveTouchPoint(0, 65, 10);
-  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  uint32 touch_move_event_id2 = SendTouchEvent();
+  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_NOT_CONSUMED,
+                                   touch_move_event_id2);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
 
   SimulateGestureScrollUpdateEvent(45, 0, 0);
   SendInputEventACK(WebInputEvent::GestureScrollUpdate,
                     INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_EQ(OVERSCROLL_EAST, overscroll_mode());
   EXPECT_EQ(OVERSCROLL_EAST, overscroll_delegate()->current_mode());
   EXPECT_EQ(65.f, overscroll_delta_x());
   EXPECT_EQ(15.f, overscroll_delegate()->delta_x());
   EXPECT_EQ(0.f, overscroll_delegate()->delta_y());
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
 
   // Send another touch event. The page should get the touch-move event, even
   // though overscroll has started.
   MoveTouchPoint(0, 55, 5);
+  uint32 touch_move_event_id3 = SendTouchEvent();
   EXPECT_EQ(OVERSCROLL_EAST, overscroll_mode());
   EXPECT_EQ(OVERSCROLL_EAST, overscroll_delegate()->current_mode());
   EXPECT_EQ(65.f, overscroll_delta_x());
   EXPECT_EQ(15.f, overscroll_delegate()->delta_x());
   EXPECT_EQ(0.f, overscroll_delegate()->delta_y());
-  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_NOT_CONSUMED,
+                                   touch_move_event_id3);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
 
   SimulateGestureScrollUpdateEvent(-10, 0, 0);
   EXPECT_EQ(0U, sink_->message_count());
   EXPECT_EQ(OVERSCROLL_EAST, overscroll_mode());
   EXPECT_EQ(OVERSCROLL_EAST, overscroll_delegate()->current_mode());
   EXPECT_EQ(55.f, overscroll_delta_x());
   EXPECT_EQ(5.f, overscroll_delegate()->delta_x());
   EXPECT_EQ(0.f, overscroll_delegate()->delta_y());
 
   PressTouchPoint(255, 5);
-  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  uint32 touch_press_event_id2 = SendTouchEvent();
+  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_NOT_CONSUMED,
+                                   touch_press_event_id2);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
 
   SimulateGestureScrollUpdateEvent(200, 0, 0);
   EXPECT_EQ(0U, sink_->message_count());
   EXPECT_EQ(OVERSCROLL_EAST, overscroll_mode());
   EXPECT_EQ(OVERSCROLL_EAST, overscroll_delegate()->current_mode());
   EXPECT_EQ(255.f, overscroll_delta_x());
   EXPECT_EQ(205.f, overscroll_delegate()->delta_x());
   EXPECT_EQ(0.f, overscroll_delegate()->delta_y());
 
   // The touch-end/cancel event should always reach the renderer if the page has
   // touch handlers.
   ReleaseTouchPoint(1);
-  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  uint32 touch_release_event_id1 = SendTouchEvent();
+  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_NOT_CONSUMED,
+                                   touch_release_event_id1);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
   ReleaseTouchPoint(0);
-  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  uint32 touch_release_event_id2 = SendTouchEvent();
+  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_NOT_CONSUMED,
+                                   touch_release_event_id2);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
 
   SimulateGestureEvent(blink::WebInputEvent::GestureScrollEnd,
                        blink::WebGestureDeviceTouchscreen);
   base::MessageLoop::current()->PostDelayedTask(
       FROM_HERE,
       base::MessageLoop::QuitClosure(),
       base::TimeDelta::FromMilliseconds(10));
   base::MessageLoop::current()->Run();
   EXPECT_EQ(1U, sink_->message_count());
@@ skipping 344 matching lines @@
                        ui::EventTimeForNow());
 
   // Construct a move with a touch id which doesn't exist.
   ui::TouchEvent invalid_move(ui::ET_TOUCH_MOVED, gfx::Point(30, 30), 1,
                               ui::EventTimeForNow());
 
   // Valid press is handled asynchronously.
   view_->OnTouchEvent(&press);
   EXPECT_TRUE(press.synchronous_handling_disabled());
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
-  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_CONSUMED);
+  AckLastSentInputEventIfNecessary(INPUT_EVENT_ACK_STATE_CONSUMED,
+                                   press.unique_event_id());
 
   // Invalid move is handled synchronously, but is consumed. It should not
   // be forwarded to the renderer.
   view_->OnTouchEvent(&invalid_move);
   EXPECT_EQ(0U, GetSentMessageCountAndResetSink());
   EXPECT_FALSE(invalid_move.synchronous_handling_disabled());
   EXPECT_TRUE(invalid_move.stopped_propagation());
 }
 
 // Checks key event codes.
@@ skipping 70 matching lines @@
 // lose track of the number of acks required.
 TEST_F(RenderWidgetHostViewAuraTest, CorrectNumberOfAcksAreDispatched) {
   view_->InitAsFullscreen(parent_view_);
   view_->Show();
   view_->UseFakeDispatcher();
 
   ui::TouchEvent press1(
       ui::ET_TOUCH_PRESSED, gfx::Point(30, 30), 0, ui::EventTimeForNow());
 
   view_->OnTouchEvent(&press1);
-  SendInputEventACK(blink::WebInputEvent::TouchStart,
-                    INPUT_EVENT_ACK_STATE_CONSUMED);
+  SendTouchEventACK(blink::WebInputEvent::TouchStart,
+                    INPUT_EVENT_ACK_STATE_CONSUMED, press1.unique_event_id());
 
   ui::TouchEvent press2(
       ui::ET_TOUCH_PRESSED, gfx::Point(20, 20), 1, ui::EventTimeForNow());
   view_->OnTouchEvent(&press2);
-  SendInputEventACK(blink::WebInputEvent::TouchStart,
-                    INPUT_EVENT_ACK_STATE_CONSUMED);
+  SendTouchEventACK(blink::WebInputEvent::TouchStart,
+                    INPUT_EVENT_ACK_STATE_CONSUMED, press2.unique_event_id());
 
   EXPECT_EQ(2U, view_->dispatcher_->GetAndResetProcessedTouchEventCount());
 }
 
 // Tests that the scroll deltas stored within the overscroll controller get
 // reset at the end of the overscroll gesture even if the overscroll threshold
 // isn't surpassed and the overscroll mode stays OVERSCROLL_NONE.
 TEST_F(RenderWidgetHostViewAuraOverscrollTest, ScrollDeltasResetOnEnd) {
   SetUpOverscrollEnvironment();
   // Wheel event scroll ending with mouse move.
@@ skipping 30 matching lines @@
                     INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_EQ(OVERSCROLL_NONE, overscroll_mode());
   EXPECT_EQ(15.f, overscroll_delta_x());
   EXPECT_EQ(-5.f, overscroll_delta_y());
   SimulateGestureFlingStartEvent(0.f, 0.1f, blink::WebGestureDeviceTouchpad);
   EXPECT_EQ(0.f, overscroll_delta_x());
   EXPECT_EQ(0.f, overscroll_delta_y());
 }
 
 }  // namespace content