Extract touch handling logic from EventHandler

third_party/WebKit/Source/core/input/TouchEventManager.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 TouchEventManager_h
+#define TouchEventManager_h
+
+#include "core/CoreExport.h"
+#include "core/events/PointerEventFactory.h"
+#include "platform/UserGestureIndicator.h"
+#include "public/platform/WebInputEventResult.h"
+#include "wtf/Allocator.h"
+#include "wtf/HashMap.h"
+
+
+namespace blink {
+
+class LocalFrame;
+class Document;
+class PlatformTouchEvent;
+class PointerEventWithTarget;
+
+// This class takes care of dispatching all touch events and their properties.
+class CORE_EXPORT TouchEventManager {
+    DISALLOW_NEW();
+public:
+    class TouchInfo {
+        DISALLOW_NEW_EXCEPT_PLACEMENT_NEW();
+    public:
+        DEFINE_INLINE_TRACE()
+        {
+            visitor->trace(touchNode);
+            visitor->trace(targetFrame);
+        }
+
+        PlatformTouchPoint point;
+        Member<Node> touchNode;
+        Member<LocalFrame> targetFrame;
+        FloatPoint adjustedPagePoint;
+        FloatSize adjustedRadius;
+        bool knownTarget;
+        String region;
+    };
+
+    explicit TouchEventManager(LocalFrame*);
+    ~TouchEventManager();
+    DECLARE_TRACE();
+
+    WebInputEventResult handleTouchEvent(

[mustaq, 2016/04/20 15:40:01]

Since handlerTouchEvent() is the main service provided by this class, is
"TouchEventHandler" a more appropriate name?

[Navid Zolghadr, 2016/04/25 15:48:32]

I just wanted to follow the PointerEventManager class naming as both of the
classes keep track of the states and stuff like that. Let me do the renaming of
all in one change maybe later if you like to have it all *Handler.

+        const PlatformTouchEvent&,
+        HeapVector<TouchInfo>&);
+
+    // Resets the internal state of this object.
+    void clear();
+
+    // Returns whether there is any touch on the screen.
+    bool isAnyTouchActive();
+
+private:
+
+    void updateTargetAndRegionMapsForTouchStarts(HeapVector<TouchInfo>&);
+    void setAllPropertiesofTouchInfos(HeapVector<TouchInfo>&);

[mustaq, 2016/04/20 15:40:01]

s/of/Of/

+
+    WebInputEventResult dispatchTouchEvents(
+        const PlatformTouchEvent&,
+        HeapVector<TouchInfo>&,
+        bool allTouchReleased);
+
+
+    // NOTE: If adding a new field to this class please ensure that it is
+    // cleared in |PointerEventManager::clear()|.
+
+    const Member<LocalFrame> m_frame;
+
+    // The target of each active touch point indexed by the touch ID.
+    using TouchTargetMap = HeapHashMap<unsigned, Member<Node>, DefaultHash<unsigned>::Hash, WTF::UnsignedWithZeroKeyHashTraits<unsigned>>;
+    TouchTargetMap m_targetForTouchID;
+    using TouchRegionMap = HeapHashMap<unsigned, String, DefaultHash<unsigned>::Hash, WTF::UnsignedWithZeroKeyHashTraits<unsigned>>;
+    TouchRegionMap m_regionForTouchID;
+
+    bool m_touchPressed;
+
+    // If set, the document of the active touch sequence. Unset if no touch sequence active.
+    Member<Document> m_touchSequenceDocument;
+    RefPtr<UserGestureToken> m_touchSequenceUserGestureToken;
+
+};
+
+} // namespace blink
+
+WTF_ALLOW_INIT_WITH_MEM_FUNCTIONS(blink::TouchEventManager::TouchInfo);
+
+#endif // TouchEventManager_h