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

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

 // Copyright 2016 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.
 
 #ifndef PointerEventFactory_h
 #define PointerEventFactory_h
 
 #include "core/CoreExport.h"
 #include "core/events/PointerEvent.h"
 #include "public/platform/WebPointerProperties.h"
@@ skipping 22 matching lines @@
         const AtomicString& mouseEventName, const PlatformMouseEvent&,
         PassRefPtrWillBeRawPtr<EventTarget> relatedTarget,
         PassRefPtrWillBeRawPtr<AbstractView>);
 
     PassRefPtrWillBeRawPtr<PointerEvent> create(const AtomicString& type,
         const PlatformTouchPoint&, PlatformEvent::Modifiers,
         const double width, const double height,
         const double clientX, const double clientY);
 
     PassRefPtrWillBeRawPtr<PointerEvent> createPointerCancelEvent(
-        const PlatformTouchPoint&);
+        const int pointerId, const WebPointerProperties::PointerType);
 
     // For creating capture events (i.e got/lostpointercapture)
     PassRefPtrWillBeRawPtr<PointerEvent> createPointerCaptureEvent(
         PassRefPtrWillBeRawPtr<PointerEvent>,
         const AtomicString&);
 
     // For creating transition events (i.e pointerout/leave/over/enter)
     PassRefPtrWillBeRawPtr<PointerEvent> createPointerTransitionEvent(
         PassRefPtrWillBeRawPtr<PointerEvent>,
         const AtomicString&,
         PassRefPtrWillBeRawPtr<EventTarget>);
 
     // 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, the 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);

[tdresser, 2016/04/01 14:50:24]

We don't need WillBe types anymore, do we?
Might as well just say HeapVector.

[mustaq, 2016/04/01 18:31:05]

Yes, good catch. Let's save one search-replace from haraken's plate ;-)

 
     // Returns whether a pointer id exists and active
     bool isActive(const int);
 
     // Returns whether a pointer id exists and has at least one pressed button
     bool isActiveButtonsState(const int);
 
 private:
     typedef WTF::UnsignedWithZeroKeyHashTraits<int> UnsignedHash;
     typedef struct IncomingId : public std::pair<int, int> {
         IncomingId() {}
         IncomingId(WebPointerProperties::PointerType pointerType,
             int rawId)
             : std::pair<int, int>(static_cast<int>(pointerType), rawId) {}
         int pointerType() const {return first;}
         int rawId() const {return second;}
     } IncomingId;
     typedef struct PointerAttributes {
         IncomingId incomingId;
         bool isActiveButtons;
         PointerAttributes() {}
         PointerAttributes(IncomingId incomingId, unsigned isActiveButtons)
         : incomingId(incomingId)
         , isActiveButtons(isActiveButtons) {}
     } PointerAttributes;
 
     int addIdAndActiveButtons(const IncomingId, bool isActiveButtons);
     bool isPrimary(const int) const;
-    void setIdTypeButtons(PointerEventInit &, const WebPointerProperties &,
+    void setIdTypeButtons(PointerEventInit&, const WebPointerProperties&,
         unsigned buttons);
+    void setBubblesAndCancelable(PointerEventInit&, const AtomicString& type);
 
     static const int s_invalidId;
     static const int s_mouseId;
 
     int m_currentId;
     HashMap<IncomingId, int, WTF::PairHash<int, int>, WTF::PairHashTraits<UnsignedHash, UnsignedHash>> m_pointerIncomingIdMapping;
     HashMap<int, PointerAttributes, WTF::IntHash<int>, UnsignedHash> m_pointerIdMapping;
     int m_primaryId[static_cast<int>(WebPointerProperties::PointerType::LastEntry) + 1];
     int m_idCount[static_cast<int>(WebPointerProperties::PointerType::LastEntry) + 1];
 };
 
 } // namespace blink
 
 #endif // PointerEventFactory_h