Refactor compositor event handling path to be callback-based

ui/events/blink/input_handler_proxy_unittest.cc

Index: ui/events/blink/input_handler_proxy_unittest.cc
diff --git a/ui/events/blink/input_handler_proxy_unittest.cc b/ui/events/blink/input_handler_proxy_unittest.cc
index 28a95d7df73c74bfefae01ddbabf96cc545b098f..fdd3af0dd1cc78a50f142d20e132aa2ae7c44531 100644
--- a/ui/events/blink/input_handler_proxy_unittest.cc
+++ b/ui/events/blink/input_handler_proxy_unittest.cc
@@ -223,11 +223,12 @@ class MockInputHandlerProxyClient
         blink::WebFloatSize(cumulative_scroll.width, cumulative_scroll.height));
   }
 
-  MOCK_METHOD4(DidOverscroll,
+  MOCK_METHOD5(DidOverscroll,
                void(const gfx::Vector2dF& accumulated_overscroll,
                     const gfx::Vector2dF& latest_overscroll_delta,
                     const gfx::Vector2dF& current_fling_velocity,
-                    const gfx::PointF& causal_event_viewport_point));
+                    const gfx::PointF& causal_event_viewport_point,
+                    bool bundle_ack_with_triggering_event));
   void DidStartFlinging() override {}
   void DidStopFlinging() override {}
   void DidAnimateForInput() override {}
@@ -1707,11 +1708,10 @@ TEST_P(InputHandlerProxyTest, GestureFlingStopsAtContentEdge) {
       .WillOnce(testing::Return(overscroll));
   EXPECT_CALL(
       mock_client_,
-      DidOverscroll(
-          overscroll.accumulated_root_overscroll,
-          overscroll.unused_scroll_delta,
-          testing::Property(&gfx::Vector2dF::y, testing::Lt(0)),
-          testing::_));
+      DidOverscroll(overscroll.accumulated_root_overscroll,
+                    overscroll.unused_scroll_delta,
+                    testing::Property(&gfx::Vector2dF::y, testing::Lt(0)),
+                    testing::_, testing::_));
   EXPECT_CALL(mock_input_handler_, ScrollEnd(testing::_));
   EXPECT_SET_NEEDS_ANIMATE_INPUT(1);
   time += base::TimeDelta::FromMilliseconds(100);
@@ -1865,11 +1865,10 @@ TEST_P(InputHandlerProxyTest, GestureFlingCancelledAfterBothAxesStopScrolling) {
       .WillOnce(testing::Return(overscroll));
   EXPECT_CALL(
       mock_client_,
-      DidOverscroll(
-          overscroll.accumulated_root_overscroll,
-          overscroll.unused_scroll_delta,
-          testing::Property(&gfx::Vector2dF::y, testing::Lt(0)),
-          testing::_));
+      DidOverscroll(overscroll.accumulated_root_overscroll,
+                    overscroll.unused_scroll_delta,
+                    testing::Property(&gfx::Vector2dF::y, testing::Lt(0)),
+                    testing::_, testing::_));
   EXPECT_SET_NEEDS_ANIMATE_INPUT(1);
   time += base::TimeDelta::FromMilliseconds(10);
   Animate(time);
@@ -1894,11 +1893,10 @@ TEST_P(InputHandlerProxyTest, GestureFlingCancelledAfterBothAxesStopScrolling) {
       .WillOnce(testing::Return(overscroll));
   EXPECT_CALL(
       mock_client_,
-      DidOverscroll(
-          overscroll.accumulated_root_overscroll,
-          overscroll.unused_scroll_delta,
-          testing::Property(&gfx::Vector2dF::x, testing::Lt(0)),
-          testing::_));
+      DidOverscroll(overscroll.accumulated_root_overscroll,
+                    overscroll.unused_scroll_delta,
+                    testing::Property(&gfx::Vector2dF::x, testing::Lt(0)),
+                    testing::_, testing::_));
   EXPECT_CALL(mock_input_handler_, ScrollEnd(testing::_));
   time += base::TimeDelta::FromMilliseconds(10);
   Animate(time);