[Android] Perform eager gesture recognition on MotionEvents

content/browser/renderer_host/render_widget_host_view_android.cc

Index: content/browser/renderer_host/render_widget_host_view_android.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_android.cc b/content/browser/renderer_host/render_widget_host_view_android.cc
index c1aa70b52ef90ce1733e1576ad58885982f04060..14dd91313e3ea1581eb7956e9df6b71c64014b30 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.cc
+++ b/content/browser/renderer_host/render_widget_host_view_android.cc
@@ -1101,23 +1101,25 @@ void RenderWidgetHostViewAndroid::UnhandledWheelEvent(
 }
 
 void RenderWidgetHostViewAndroid::GestureEventAck(
-    int gesture_event_type,
+    const blink::WebGestureEvent& event,
     InputEventAckState ack_result) {
-  // Scroll events.
-  if (gesture_event_type == blink::WebInputEvent::GestureScrollBegin) {
+  if (event.type == blink::WebInputEvent::GestureScrollBegin) {
     content_view_core_->OnScrollBeginEventAck();
-  }
-  if (gesture_event_type == blink::WebInputEvent::GestureScrollUpdate &&
-      ack_result == INPUT_EVENT_ACK_STATE_CONSUMED) {
-    content_view_core_->OnScrollUpdateGestureConsumed();
-  }
-  if (gesture_event_type == blink::WebInputEvent::GestureScrollEnd) {
+  } else if (event.type == blink::WebInputEvent::GestureScrollUpdate) {
+    if (ack_result == INPUT_EVENT_ACK_STATE_CONSUMED)
+      content_view_core_->OnScrollUpdateGestureConsumed();
+  } else if (event.type == blink::WebInputEvent::GestureScrollEnd) {
     content_view_core_->OnScrollEndEventAck();
-  }
-
-  // Fling events.
-  if (gesture_event_type == blink::WebInputEvent::GestureFlingStart) {
-    content_view_core_->OnFlingStartEventAck(ack_result);
+  } else if (event.type == blink::WebInputEvent::GestureFlingStart) {
+    if (ack_result == INPUT_EVENT_ACK_STATE_NOT_CONSUMED ||
+        ack_result == INPUT_EVENT_ACK_STATE_NO_CONSUMER_EXISTS) {
+      const bool had_consumer =
+          ack_result == INPUT_EVENT_ACK_STATE_NOT_CONSUMED;
+      content_view_core_->OnUnhandledFlingStartEventAck(
+          had_consumer,
+          event.data.flingStart.velocityX,
+          event.data.flingStart.velocityY);
+    }
   }
 }
 
@@ -1241,7 +1243,6 @@ void RenderWidgetHostViewAndroid::SendTouchEvent(
     host_->ForwardTouchEventWithLatencyInfo(event, CreateLatencyInfo(event));
 }
 
-
 void RenderWidgetHostViewAndroid::SendMouseEvent(
     const blink::WebMouseEvent& event) {
   if (host_)
@@ -1367,11 +1368,6 @@ void RenderWidgetHostViewAndroid::SetContentViewCore(
     if (content_view_core_ && !using_synchronous_compositor_)
       content_view_core_->GetWindowAndroid()->AddObserver(this);
   }
-
-  // Ensure ContentsViewCore is aware of the current touch handling state, eg.
-  // in case we've already been running JS for the page as part of preload.
-  if (content_view_core_ && host_)
-    content_view_core_->HasTouchEventHandlers(host_->has_touch_handler());
 }
 
 void RenderWidgetHostViewAndroid::RunAckCallbacks() {
@@ -1383,8 +1379,6 @@ void RenderWidgetHostViewAndroid::RunAckCallbacks() {
 
 void RenderWidgetHostViewAndroid::HasTouchEventHandlers(
     bool need_touch_events) {
-  if (content_view_core_)
-    content_view_core_->HasTouchEventHandlers(need_touch_events);
 }
 
 void RenderWidgetHostViewAndroid::OnCompositingDidCommit() {