Factor out GamepadCommon base class from Gamepad and WebKitGamepad

Source/modules/gamepad/WebKitGamepad.h

 // Copyright 2014 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 WebKitGamepad_h
 #define WebKitGamepad_h
 
-#include "bindings/v8/ScriptWrappable.h"
-#include "heap/Handle.h"
-#include "public/platform/WebGamepad.h"
-#include "wtf/RefCounted.h"
+#include "modules/gamepad/Gamepad.h"
 #include "wtf/Vector.h"
-#include "wtf/text/WTFString.h"
 
 namespace WebCore {
 
-class WebKitGamepad FINAL : public RefCountedWillBeGarbageCollectedFinalized<WebKitGamepad>, public ScriptWrappable {
+// Inherit from concrete Gamepad class (instead of factoring out an abstract
+// GamepadCommon class) so Gamepad is simple (unfactored) and low-cruft.
+class WebKitGamepad : public Gamepad {
 public:
     static PassRefPtrWillBeRawPtr<WebKitGamepad> create()
     {
         return adoptRefWillBeNoop(new WebKitGamepad);
     }
-    ~WebKitGamepad();
 
     typedef Vector<float> FloatVector;
 
-    const String& id() const { return m_id; }
-    void setId(const String& id) { m_id = id; }
-
-    unsigned index() const { return m_index; }
-    void setIndex(unsigned val) { m_index = val; }
-
-    bool connected() const { return m_connected; }
-    void setConnected(bool val) { m_connected = val; }
-
-    unsigned long long timestamp() const { return m_timestamp; }
-    void setTimestamp(unsigned long long val) { m_timestamp = val; }
-
-    const String& mapping() const { return m_mapping; }
-    void setMapping(const String& val) { m_mapping = val; }
-
-    const FloatVector& axes() const { return m_axes; }
-    void setAxes(unsigned count, const float* data);
-
     const FloatVector& buttons() const { return m_buttons; }
     void setButtons(unsigned count, const blink::WebGamepadButton* data);
 
-    void trace(Visitor*);
+    void trace(Visitor*) { };
 
 private:
-    WebKitGamepad();
-    String m_id;
-    unsigned m_index;
-    bool m_connected;
-    unsigned long long m_timestamp;
-    String m_mapping;
-    FloatVector m_axes;
+    WebKitGamepad()
+    {
+        ScriptWrappable::init(this);

[haraken, 2014/03/13 06:29:39]

As discussed offline, we don't want to call ScriptWrappable::init() twice.

[Nils Barth (inactive), 2014/03/13 06:42:21]

kouhei will elaborate;
sounds like simplest/best answer is to in fact have an abstract
base class, and just call ScriptWrappable::init() in the concrete
derived classes.

+    }
     FloatVector m_buttons;
 };
 
 } // namespace WebCore
 
 #endif // WebKitGamepad_h