Notify Blink about start of gesture scroll through a queued event.

third_party/WebKit/Source/core/events/PointerEventFactory.h

Index: third_party/WebKit/Source/core/events/PointerEventFactory.h
diff --git a/third_party/WebKit/Source/core/events/PointerEventFactory.h b/third_party/WebKit/Source/core/events/PointerEventFactory.h
index 9e342217270e39a2f8f6dfefbc6292902bd4f70a..0644c4e448c251e80b8904d2eac711b4b8a6a185 100644
--- a/third_party/WebKit/Source/core/events/PointerEventFactory.h
+++ b/third_party/WebKit/Source/core/events/PointerEventFactory.h
@@ -40,7 +40,7 @@ public:
         const double clientX, const double clientY);
 
     PassRefPtrWillBeRawPtr<PointerEvent> createPointerCancel(
-        const PlatformTouchPoint&);
+        const int pointerId, const WebPointerProperties::PointerType);
 
     PassRefPtrWillBeRawPtr<PointerEvent> create(
         PassRefPtrWillBeRawPtr<PointerEvent>,
@@ -50,11 +50,13 @@ public:
     // Clear all the existing ids.
     void clear();
 
-    // Returns true if pointerEvent is removed. When a pointerEvent with a
-    // particular id is removed that id is considered free even though there
-    // might have been other PointerEvents that were generated with the same id
-    // before.
-    bool remove(const PassRefPtrWillBeRawPtr<PointerEvent>);
+    // When a particular pointerId is removed that id is considered free even
+    // though there might have been other PointerEvents that were generated with
+    // the same id before.
+    bool remove(const int);
+
+    // Returns all ids of the given pointerType.
+    WillBeHeapVector<int> getPointerIdsOfType(WebPointerProperties::PointerType);
 
     // Returns whether a pointer id exists and active
     bool isActive(const int);