Added PointerEvent firing on touch events.

Source/core/events/PointerIdManager.h

Index: Source/core/events/PointerIdManager.h
diff --git a/Source/core/events/PointerIdManager.h b/Source/core/events/PointerIdManager.h
new file mode 100644
index 0000000000000000000000000000000000000000..de0462b891d72faecb09e888e14260b3ff12343b
--- /dev/null
+++ b/Source/core/events/PointerIdManager.h
@@ -0,0 +1,40 @@
+// Copyright 2015 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 PointerIdManager_h
+#define PointerIdManager_h
+
+#include "wtf/ListHashSet.h"
+
+namespace blink {
+
+/**
+  Helper class for tracking the primary pointer id for each type of PointerEvents.
+*/
+class PointerIdManager {
+public:
+    // TODO(mustaq): Move this enum to PointerEvent.h? Change the spec to use enums?
+    enum PointerType {
+        PointerTypeUnknown = 0,
+        PointerTypeMouse,
+        PointerTypePen,
+        PointerTypeTouch,
+        PointerTypeLastEntry // Must be the last entry in the list
+    };
+
+    PointerIdManager();
+    ~PointerIdManager();
+    void clear();
+    void add(PointerType, unsigned);
+    void remove(PointerType, unsigned);
+    bool isPrimary(PointerType, unsigned);
+
+private:
+    ListHashSet<unsigned> m_ids[PointerTypeLastEntry];
+    bool m_hasPrimaryId[PointerTypeLastEntry];
+};
+
+} // namespace blink
+
+#endif // PointerIdManager_h