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 425 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;
+    InputEventAck ack(type, ack_result);
+    if (WebInputEvent::isTouchEventType(type))
+      ack.unique_touch_event_id = last_sent_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) {
     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;
 
+    SetLastSentEventIDFromSentEvent();
     SendInputEventACK(get<0>(params)->type, ack_result);
   }
 
+  void SetLastSentEventID(uint32 event_id) { last_sent_event_id_ = event_id; }

[jdduke (slow), 2015/05/07 21:11:16]

Instead of setting the id and trying to guess it, can we instead have a separate
ACK method for touches?

SendTouchEventAck(type, id, result);

And the caller is explicitly responsible for associating the proper ID?

+
+  void SetLastSentEventIDFromSentEvent() {
+    size_t count = sink_->message_count();
+    for (size_t i = 0; i < count; ++i) {
+      const WebInputEvent* input_event =
+          GetInputEventFromMessage(*sink_->GetMessageAt(i));
+      last_sent_event_id_ =
+          WebInputEventTraits::GetUniqueTouchEventId(*input_event);
+    }
+  }
+
  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_;
   scoped_ptr<aura::test::AuraTestHelper> aura_test_helper_;
   scoped_ptr<BrowserContext> browser_context_;
   MockRenderWidgetHostDelegate delegate_;
   MockRenderProcessHost* process_host_;
 
   // Tests should set these to NULL if they've already triggered their
   // destruction.
   RenderWidgetHostImpl* parent_host_;
   RenderWidgetHostViewAura* parent_view_;
 
   // Tests should set these to NULL if they've already triggered their
   // destruction.
   RenderWidgetHostImpl* widget_host_;
   FakeRenderWidgetHostViewAura* view_;
 
   IPC::TestSink* sink_;
 
+  uint32 last_sent_event_id_;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAuraTest);
 };
 
 // Helper class to instantiate RenderWidgetHostViewGuest which is backed
 // by an aura platform view.
 class RenderWidgetHostViewGuestAuraTest : public RenderWidgetHostViewAuraTest {
  public:
   RenderWidgetHostViewGuestAuraTest() {
     // Use RWH::Shutdown to destroy RWH, instead of deleting.
@@ skipping 585 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);
+  ack.unique_touch_event_id = 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 1655 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);
+  SetLastSentEventIDFromSentEvent();
   SendInputEventACK(WebInputEvent::TouchStart,
                     INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
 
   MoveTouchPoint(0, 20, 5);
+  SetLastSentEventIDFromSentEvent();
   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());
@@ skipping 507 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);
+  SetLastSentEventID(press1.unique_event_id());
   SendInputEventACK(blink::WebInputEvent::TouchStart,
                     INPUT_EVENT_ACK_STATE_CONSUMED);
 
   ui::TouchEvent press2(
       ui::ET_TOUCH_PRESSED, gfx::Point(20, 20), 1, ui::EventTimeForNow());
   view_->OnTouchEvent(&press2);
+  SetLastSentEventID(press2.unique_event_id());
   SendInputEventACK(blink::WebInputEvent::TouchStart,
                     INPUT_EVENT_ACK_STATE_CONSUMED);
 
   EXPECT_EQ(2U, view_->dispatcher_->processed_touch_event_count());
 }
 
 // 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) {
@@ skipping 32 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