Reenable the tap down gesture.

content/browser/renderer_host/input/gesture_event_filter_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 <vector>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 552 matching lines @@
   EXPECT_FALSE(FlingInProgress());
   EXPECT_EQ(5U, GestureEventLastQueueEventSize());
 }
 
 INSTANTIATE_TEST_CASE_P(AllSources,
                         GestureEventFilterWithSourceTest,
                         testing::Values(WebGestureEvent::Touchscreen,
                                         WebGestureEvent::Touchpad));
 #endif  // GTEST_HAS_PARAM_TEST
 
-// Test that GestureShowPress events don't wait for ACKs.
-TEST_F(GestureEventFilterTest, GestureShowPressIgnoresAck) {
+// Test that GestureShowPress and GestureTapDown events don't wait for ACKs.
+TEST_F(GestureEventFilterTest, GestureShowPressAndTapDownIgnoreAck) {
   SimulateGestureEvent(WebInputEvent::GestureShowPress,
                        WebGestureEvent::Touchscreen);
 
   EXPECT_EQ(1U, GetAndResetSentGestureEventCount());
   EXPECT_EQ(0U, GestureEventLastQueueEventSize());
 
   SimulateGestureEvent(WebInputEvent::GestureShowPress,
                        WebGestureEvent::Touchscreen);
 
   EXPECT_EQ(1U, GetAndResetSentGestureEventCount());
   EXPECT_EQ(0U, GestureEventLastQueueEventSize());
 
   SimulateGestureEvent(WebInputEvent::GestureShowPress,
                        WebGestureEvent::Touchscreen);
 
   EXPECT_EQ(1U, GetAndResetSentGestureEventCount());
-  // The show press events will have escaped the queue, since they ignore acks.
+  EXPECT_EQ(0U, GestureEventLastQueueEventSize());
+
+  SimulateGestureEvent(WebInputEvent::GestureTapDown,
+                       WebGestureEvent::Touchscreen);
+
+  EXPECT_EQ(1U, GetAndResetSentGestureEventCount());
+  // The show press and tap down events will have escaped the queue, since they
+  // ignore acks.
   EXPECT_EQ(0U, GestureEventLastQueueEventSize());
 }
 
 // Test that GestureShowPress events don't get out of order due to
 // ignoring their acks.
 TEST_F(GestureEventFilterTest, GestureShowPressIsInOrder) {
   SimulateGestureEvent(WebInputEvent::GestureTap,
                        WebGestureEvent::Touchscreen);
 
   EXPECT_EQ(1U, GetAndResetSentGestureEventCount());
@@ skipping 133 matching lines @@
   gesture_event.data.flingStart.velocityX = 0.f;
   gesture_event.data.flingStart.velocityY = 0.f;
   ASSERT_EQ(0U, GetAndResetSentGestureEventCount());
   ASSERT_EQ(0U, GestureEventLastQueueEventSize());
   EXPECT_FALSE(SimulateGestureEvent(gesture_event));
   EXPECT_EQ(0U, GetAndResetSentGestureEventCount());
   EXPECT_EQ(0U, GestureEventLastQueueEventSize());
 }
 
 }  // namespace content