Re-enable Eager Gesture Recognition on Aura

content/browser/renderer_host/render_widget_host_view_aura.cc

Index: content/browser/renderer_host/render_widget_host_view_aura.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.cc b/content/browser/renderer_host/render_widget_host_view_aura.cc
index 9d6b2e2e662ce5287583e907cba01822f41e097e..3bf29e7ddae0b8bfbc3ef9a627f2609fd18480c8 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.cc
+++ b/content/browser/renderer_host/render_widget_host_view_aura.cc
@@ -2037,23 +2037,32 @@ void RenderWidgetHostViewAura::OnTouchEvent(ui::TouchEvent* event) {
     return;
 
   // Update the touch event first.
-  blink::WebTouchPoint* point = UpdateWebTouchEventFromUIEvent(*event,
-                                                                &touch_event_);
-
-  // Forward the touch event only if a touch point was updated, and there's a
-  // touch-event handler in the page, and no other touch-event is in the queue.
-  // It is important to always consume the event if there is a touch-event
-  // handler in the page, or some touch-event is already in the queue, even if
-  // no point has been updated, to make sure that this event does not get
-  // processed by the gesture recognizer before the events in the queue.
-  if (host_->ShouldForwardTouchEvent())
-    event->StopPropagation();
+  blink::WebTouchPoint* point =
+      UpdateWebTouchEventFromUIEvent(*event, &touch_event_);
 
-  if (point) {
-    if (host_->ShouldForwardTouchEvent())
-      host_->ForwardTouchEventWithLatencyInfo(touch_event_, *event->latency());
-    UpdateWebTouchEventAfterDispatch(&touch_event_, point);
+  if (!point && host_->ShouldForwardTouchEvent()) {
+    event->DisableSynchronousHandling();
+    // Ignore the most recent touch event, as it wasn't valid.
+    DCHECK(window_->GetHost());
+    window_->GetHost()->dispatcher()->IgnoreLastTouchEvent(window_);

[jdduke (slow), 2014/11/20 19:49:16]

Is this better than calling
|ui::GestureRecognizer::Get()->IgnoreLastTouchEvent(window_);| directly?

[tdresser, 2014/11/21 13:25:21]

Done.

I was thinking it was better from a layering perspective, but I've changed my
mind.

   }
+
+  if (!point)
+    return;
+
+  // Forward the touch event only if a touch point was updated, and
+  // there's a touch-event handler in the page, and no other
+  // touch-event is in the queue. It is important to always mark
+  // events as being handled asynchronously if there is a touch-event
+  // handler in the page, or some touch-event is already in the queue,
+  // even if no point has been updated. This ensures that this event
+  // does not get processed by the gesture recognizer before events
+  // currently awaiting dispatch in the touch queue.
+  if (host_->ShouldForwardTouchEvent()) {
+    event->DisableSynchronousHandling();
+    host_->ForwardTouchEventWithLatencyInfo(touch_event_, *event->latency());
+  }
+  UpdateWebTouchEventAfterDispatch(&touch_event_, point);
 }
 
 void RenderWidgetHostViewAura::OnGestureEvent(ui::GestureEvent* event) {