[Tracking Patch] Unified gesture detection

content/browser/renderer_host/input/touch_disposition_gesture_filter.cc

Index: content/browser/renderer_host/input/touch_disposition_gesture_filter.cc
diff --git a/content/browser/renderer_host/input/touch_disposition_gesture_filter.cc b/content/browser/renderer_host/input/touch_disposition_gesture_filter.cc
index 36de573810acd82f49292c4dc797bc485433b556..3fb27cd4fe815ce855dea8f1c9355633aa53a892 100644
--- a/content/browser/renderer_host/input/touch_disposition_gesture_filter.cc
+++ b/content/browser/renderer_host/input/touch_disposition_gesture_filter.cc
@@ -105,7 +105,8 @@ TouchDispositionGestureFilter::TouchDispositionGestureFilter(
     TouchDispositionGestureFilterClient* client)
     : client_(client),
       needs_tap_ending_event_(false),
-      needs_fling_ending_event_(false) {
+      needs_fling_ending_event_(false),
+      needs_scroll_ending_event_(false) {
   DCHECK(client_);
 }
 
@@ -146,6 +147,7 @@ void TouchDispositionGestureFilter::OnTouchEventAck(
   if (Head().IsEmpty()) {
     CancelTapIfNecessary();
     CancelFlingIfNecessary();
+    EndScrollIfNecessary();
     last_event_of_type_dropped_.clear();
     sequences_.pop();
   }
@@ -194,6 +196,8 @@ void TouchDispositionGestureFilter::FilterAndSendPacket(
 }
 
 void TouchDispositionGestureFilter::SendGesture(const WebGestureEvent& event) {
+  // TODO(jdduke): Factor out gesture stream reparation code into a standalone
+  // utility class.
   switch (event.type) {
     case WebInputEvent::GestureLongTap:
       CancelTapIfNecessary();
@@ -212,10 +216,16 @@ void TouchDispositionGestureFilter::SendGesture(const WebGestureEvent& event) {
     case WebInputEvent::GestureScrollBegin:
       CancelTapIfNecessary();
       CancelFlingIfNecessary();
+      EndScrollIfNecessary();
+      needs_scroll_ending_event_ = true;
+      break;
+    case WebInputEvent::GestureScrollEnd:
+      needs_scroll_ending_event_ = false;
       break;
     case WebInputEvent::GestureFlingStart:
       CancelFlingIfNecessary();
       needs_fling_ending_event_ = true;
+      needs_scroll_ending_event_ = false;
       break;
     case WebInputEvent::GestureFlingCancel:
       needs_fling_ending_event_ = false;
@@ -242,6 +252,14 @@ void TouchDispositionGestureFilter::CancelFlingIfNecessary() {
   DCHECK(!needs_fling_ending_event_);
 }
 
+void TouchDispositionGestureFilter::EndScrollIfNecessary() {
+  if (!needs_scroll_ending_event_)
+    return;
+
+  SendGesture(CreateGesture(WebInputEvent::GestureScrollEnd));
+  DCHECK(!needs_scroll_ending_event_);
+}
+
 // TouchDispositionGestureFilter::GestureSequence
 
 TouchDispositionGestureFilter::GestureSequence::GestureHandlingState::