Coalesce async touch move events until the ack back from render

content/browser/renderer_host/input/input_router_impl_unittest.cc

Index: content/browser/renderer_host/input/input_router_impl_unittest.cc
diff --git a/content/browser/renderer_host/input/input_router_impl_unittest.cc b/content/browser/renderer_host/input/input_router_impl_unittest.cc
index f56991892266ceeca85f3a84ec97a7d01d5d3f37..aa07d6061c28529f1a7e84f7754bd0d6482f35b3 100644
--- a/content/browser/renderer_host/input/input_router_impl_unittest.cc
+++ b/content/browser/renderer_host/input/input_router_impl_unittest.cc
@@ -961,11 +961,11 @@ TEST_F(InputRouterImplTest, UnhandledWheelEvent) {
 TEST_F(InputRouterImplTest, TouchTypesIgnoringAck) {
   OnHasTouchEventHandlers(true);
   // Only acks for TouchCancel should always be ignored.
-  ASSERT_FALSE(WebInputEventTraits::IgnoresAckDisposition(
+  ASSERT_TRUE(WebInputEventTraits::WillReceiveAckFromRenderer(
       GetEventWithType(WebInputEvent::TouchStart)));
-  ASSERT_FALSE(WebInputEventTraits::IgnoresAckDisposition(
+  ASSERT_TRUE(WebInputEventTraits::WillReceiveAckFromRenderer(
       GetEventWithType(WebInputEvent::TouchMove)));
-  ASSERT_FALSE(WebInputEventTraits::IgnoresAckDisposition(
+  ASSERT_TRUE(WebInputEventTraits::WillReceiveAckFromRenderer(
       GetEventWithType(WebInputEvent::TouchEnd)));
 
   // Precede the TouchCancel with an appropriate TouchStart;
@@ -1024,7 +1024,8 @@ TEST_F(InputRouterImplTest, GestureTypesIgnoringAck) {
   for (size_t i = 0; i < arraysize(eventTypes); ++i) {
     WebInputEvent::Type type = eventTypes[i];
     SCOPED_TRACE(WebInputEventTraits::GetName(type));
-    if (!WebInputEventTraits::IgnoresAckDisposition(GetEventWithType(type))) {
+    if (WebInputEventTraits::WillReceiveAckFromRenderer(
+            GetEventWithType(type))) {
       SimulateGestureEvent(type, blink::WebGestureDeviceTouchscreen);
       EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
       EXPECT_EQ(0U, ack_handler_->GetAndResetAckCount());
@@ -1063,8 +1064,9 @@ TEST_F(InputRouterImplTest, MouseTypesIgnoringAck) {
   for (int i = start_type; i <= end_type; ++i) {
     WebInputEvent::Type type = static_cast<WebInputEvent::Type>(i);
     int expected_in_flight_event_count =
-        WebInputEventTraits::IgnoresAckDisposition(GetEventWithType(type)) ? 0
-                                                                           : 1;
+        !WebInputEventTraits::WillReceiveAckFromRenderer(GetEventWithType(type))
+            ? 0
+            : 1;
 
     // Note: Mouse event acks are never forwarded to the ack handler, so the key
     // result here is that ignored ack types don't affect the in-flight count.
@@ -1082,7 +1084,7 @@ TEST_F(InputRouterImplTest, MouseTypesIgnoringAck) {
 }
 
 // Guard against breaking changes to the list of ignored event ack types in
-// |WebInputEventTraits::IgnoresAckDisposition|.
+// |WebInputEventTraits::WillReceiveAckFromRenderer|.
 TEST_F(InputRouterImplTest, RequiredEventAckTypes) {
   const WebInputEvent::Type kRequiredEventAckTypes[] = {
     WebInputEvent::MouseMove,
@@ -1100,7 +1102,7 @@ TEST_F(InputRouterImplTest, RequiredEventAckTypes) {
   };
   for (size_t i = 0; i < arraysize(kRequiredEventAckTypes); ++i) {
     const WebInputEvent::Type required_ack_type = kRequiredEventAckTypes[i];
-    EXPECT_FALSE(WebInputEventTraits::IgnoresAckDisposition(
+    ASSERT_TRUE(WebInputEventTraits::WillReceiveAckFromRenderer(
         GetEventWithType(required_ack_type)));
   }
 }
@@ -1518,7 +1520,7 @@ TEST_F(InputRouterImplTest, DoubleTapGestureDependsOnFirstTap) {
                        blink::WebGestureDeviceTouchscreen);
   EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
   // This test will become invalid if GestureTap stops requiring an ack.
-  ASSERT_FALSE(WebInputEventTraits::IgnoresAckDisposition(
+  ASSERT_TRUE(WebInputEventTraits::WillReceiveAckFromRenderer(
       GetEventWithType(WebInputEvent::GestureTap)));
   EXPECT_EQ(2, client_->in_flight_event_count());
   SendInputEventACK(WebInputEvent::GestureTap,
@@ -1546,7 +1548,7 @@ TEST_F(InputRouterImplTest, DoubleTapGestureDependsOnFirstTap) {
   SimulateGestureEvent(WebInputEvent::GestureDoubleTap,
                        blink::WebGestureDeviceTouchscreen);
   // This test will become invalid if GestureDoubleTap stops requiring an ack.
-  ASSERT_FALSE(WebInputEventTraits::IgnoresAckDisposition(
+  ASSERT_TRUE(WebInputEventTraits::WillReceiveAckFromRenderer(
       GetEventWithType(WebInputEvent::GestureDoubleTap)));
   EXPECT_EQ(1, client_->in_flight_event_count());
   SendInputEventACK(WebInputEvent::GestureTap, INPUT_EVENT_ACK_STATE_CONSUMED);