Coalesce async touch move events until the ack back from render

content/browser/renderer_host/render_widget_host_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 "base/basictypes.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/shared_memory.h"
 #include "base/timer/timer.h"
@@ skipping 441 matching lines @@
 
   virtual void ConfigureView(TestView* view) {
   }
 
   int64 GetLatencyComponentId() {
     return host_->GetLatencyComponentId();
   }
 
   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);
     host_->OnMessageReceived(InputHostMsg_HandleInputEvent_ACK(0, ack));
   }
 
+  uint32 LastSentEventID() {
+    uint32 last_sent_event_id = 0;
+    size_t count = process_->sink().message_count();
+    DCHECK_GT(count, 0U);
+    for (size_t i = 0; i < count; ++i) {
+      const WebInputEvent* input_event =
+          GetInputEventFromMessage(*process_->sink().GetMessageAt(i));
+      last_sent_event_id =
+          WebInputEventTraits::GetUniqueTouchEventId(*input_event);
+    }
+    return last_sent_event_id;
+  }
+
   double GetNextSimulatedEventTimeSeconds() {
     last_simulated_event_time_seconds_ += simulated_event_time_delta_seconds_;
     return last_simulated_event_time_seconds_;
   }
 
   void SimulateKeyboardEvent(WebInputEvent::Type type) {
     SimulateKeyboardEvent(type, 0);
   }
 
   void SimulateKeyboardEvent(WebInputEvent::Type type, int modifiers) {
@@ skipping 951 matching lines @@
                                       blink::WebGestureDeviceTouchscreen,
                                       ui::LatencyInfo());
   CheckLatencyInfoComponentInMessage(
       process_, GetLatencyComponentId(), WebInputEvent::GestureScrollUpdate);
   SendInputEventACK(WebInputEvent::GestureScrollUpdate,
                     INPUT_EVENT_ACK_STATE_CONSUMED);
 
   // Tests RWHI::ForwardTouchEventWithLatencyInfo().
   PressTouchPoint(0, 1);
   SendTouchEvent();
+  InputEventAck ack(WebInputEvent::TouchStart, INPUT_EVENT_ACK_STATE_CONSUMED);
+  ack.unique_touch_event_id = LastSentEventID();
+  host_->OnMessageReceived(InputHostMsg_HandleInputEvent_ACK(0, ack));
   CheckLatencyInfoComponentInMessage(
       process_, GetLatencyComponentId(), WebInputEvent::TouchStart);
-  SendInputEventACK(WebInputEvent::TouchStart, INPUT_EVENT_ACK_STATE_CONSUMED);
 }
 
 TEST_F(RenderWidgetHostTest, RendererExitedResetsInputRouter) {
   // RendererExited will delete the view.
   host_->SetView(new TestView(host_.get()));
   host_->RendererExited(base::TERMINATION_STATUS_PROCESS_CRASHED, -1);
 
   // Make sure the input router is in a fresh state.
   ASSERT_FALSE(host_->input_router()->HasPendingEvents());
 }
@@ skipping 41 matching lines @@
   // Having an initial size set means that the size information had been sent
   // with the reqiest to new up the RenderView and so subsequent WasResized
   // calls should not result in new IPC (unless the size has actually changed).
   host_->WasResized();
   EXPECT_FALSE(process_->sink().GetUniqueMessageMatching(ViewMsg_Resize::ID));
   EXPECT_EQ(initial_size_, host_->old_resize_params_->new_size);
   EXPECT_TRUE(host_->resize_ack_pending_);
 }
 
 }  // namespace content