Track whether a scroll sequence has been partially prevented

content/browser/android/overscroll_controller_android.cc

 // Copyright 2014 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 "content/browser/android/overscroll_controller_android.h"
 
 #include "base/android/build_info.h"
 #include "base/bind.h"
 #include "cc/layers/layer.h"
 #include "cc/output/compositor_frame_metadata.h"
@@ skipping 109 matching lines @@
   // The overscroll effect requires an explicit release signal that may not be
   // sent from the renderer compositor.
   if (event.type == blink::WebInputEvent::GestureScrollEnd ||
       event.type == blink::WebInputEvent::GestureFlingStart) {
     OnOverscrolled(DidOverscrollParams());
   }
 
   if (event.type == blink::WebInputEvent::GestureScrollUpdate) {
     // The effect should only be allowed if both the causal touch events go
     // unconsumed and the generated scroll events go unconsumed.
-    // TODO(jdduke): Prevent activation if the first touchmove was consumed,
-    // i.e., the first GSU was prevented.
-    bool consumed = ack_result == INPUT_EVENT_ACK_STATE_CONSUMED;
+    bool consumed = ack_result == INPUT_EVENT_ACK_STATE_CONSUMED ||
+                    event.data.scrollUpdate.previousUpdateInSequencePrevented;
     refresh_effect_.OnScrollUpdateAck(consumed);
   }
 }
 
 void OverscrollControllerAndroid::OnOverscrolled(
     const DidOverscrollParams& params) {
   if (!enabled_)
     return;
 
   if (refresh_effect_.IsActive() ||
@@ skipping 75 matching lines @@
 
 bool OverscrollControllerAndroid::IsStillRefreshing() const {
   return triggered_refresh_active_;
 }
 
 void OverscrollControllerAndroid::SetNeedsAnimate() {
   compositor_->SetNeedsAnimate();
 }
 
 }  // namespace content