Merging of touch event ack ids was inconsistent.

content/renderer/input/main_thread_event_queue_unittest.cc

 // Copyright 2016 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 <stddef.h>
 
 #include <new>
 #include <utility>
 #include <vector>
 
@@ skipping 325 matching lines @@
   HandleEvent(kEvents[1], INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   HandleEvent(kEvents[2], INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   HandleEvent(kEvents[3], INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
 
   EXPECT_EQ(2u, event_queue().size());
   EXPECT_TRUE(main_task_runner_->HasPendingTask());
   RunPendingTasksWithSimulatedRaf();
 
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(2u, additional_acked_events_.size());
-  EXPECT_EQ(kEvents[2].uniqueTouchEventId, additional_acked_events_.at(0));
-  EXPECT_EQ(kEvents[3].uniqueTouchEventId, additional_acked_events_.at(1));
+  EXPECT_EQ(kEvents[1].uniqueTouchEventId, additional_acked_events_.at(0));
+  EXPECT_EQ(kEvents[2].uniqueTouchEventId, additional_acked_events_.at(1));
+
+  const WebTouchEvent* last_touch_event =
+      static_cast<const WebTouchEvent*>(handled_events_.at(1).eventPointer());
+  EXPECT_EQ(kEvents[3].uniqueTouchEventId,
+            last_touch_event->uniqueTouchEventId);
 
   HandleEvent(kEvents[1], INPUT_EVENT_ACK_STATE_SET_NON_BLOCKING);
   HandleEvent(kEvents[2], INPUT_EVENT_ACK_STATE_SET_NON_BLOCKING);
   HandleEvent(kEvents[3], INPUT_EVENT_ACK_STATE_SET_NON_BLOCKING);
   EXPECT_EQ(1u, event_queue().size());
   RunPendingTasksWithSimulatedRaf();
   histogram_tester.ExpectUniqueSample(kCoalescedCountHistogram, 2, 2);
 }
 
 TEST_P(MainThreadEventQueueTest, InterleavedEvents) {
@@ skipping 167 matching lines @@
   SyntheticWebTouchEvent kEvents[2];
   kEvents[0].PressPoint(10, 10);
   kEvents[0].MovePoint(0, 50, 50);
   kEvents[1].PressPoint(10, 10);
   kEvents[1].MovePoint(0, 20, 20);
   kEvents[0].dispatchType = WebInputEvent::EventNonBlocking;
 
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
   EXPECT_EQ(0u, event_queue().size());
 
-  // Send a continuous input event (ack required) and then
-  // a discrete event. The events should coalesce together
+  // Send a discrete input event and then a continuous
+  // (ack required)  event. The events should coalesce together
   // and a post task should be on the queue at the end.
+  HandleEvent(kEvents[1], INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
+  EXPECT_EQ(1u, event_queue().size());
+  EXPECT_FALSE(main_task_runner_->HasPendingTask());
+  EXPECT_TRUE(needs_main_frame_);
   HandleEvent(kEvents[0], INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   EXPECT_EQ(1u, event_queue().size());
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
   EXPECT_TRUE(needs_main_frame_);
-  HandleEvent(kEvents[1], INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
-  EXPECT_EQ(1u, event_queue().size());
-  EXPECT_FALSE(main_task_runner_->HasPendingTask());
-  EXPECT_TRUE(needs_main_frame_);
   RunPendingTasksWithSimulatedRaf();
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(1u, additional_acked_events_.size());
   additional_acked_events_.clear();
 
   // Send a non-cancelable ack required event, and then a non-ack
   // required event they should be coalesced together.
   EXPECT_TRUE(HandleEvent(kEvents[0], INPUT_EVENT_ACK_STATE_NOT_CONSUMED));
   EXPECT_EQ(1u, event_queue().size());
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
@@ skipping 214 matching lines @@
       "MainThreadResponsivenessScrollIntervention", "Control");
   queue_ = new MainThreadEventQueue(kTestRoutingID,
                                     &dummy_main_thread_event_queue_client_,
                                     main_task_runner_, &renderer_scheduler_);
   EXPECT_FALSE(enable_non_blocking_due_to_main_thread_responsiveness_flag());
   EXPECT_EQ(base::TimeDelta::FromMilliseconds(0),
             main_thread_responsiveness_threshold());
 }
 
 }  // namespace content