Add an API to report debugName in GraphicsLayer

public/platform/WebLayer.h

Index: public/platform/WebLayer.h
diff --git a/public/platform/WebLayer.h b/public/platform/WebLayer.h
index a21ffedef919a12eec60ab09da0e9ccec60515e9..edcea5137bbdc03ae3310aa3378ffddd44f7217e 100644
--- a/public/platform/WebLayer.h
+++ b/public/platform/WebLayer.h
@@ -48,7 +48,15 @@ struct WebFloatRect;
 struct WebLayerPositionConstraint;
 struct WebSize;
 
-class WebLayerImpl;
+class WebLayer;
+
+class WebLayerClient {

[enne (OOO), 2013/07/30 17:31:05]

Can you put this interface in a separate file, like WebLayerScrollClient and
WebContentLayerClient both are?

[qiankun, 2013/07/31 11:16:28]

Done.

+    public:

[enne (OOO), 2013/07/30 17:31:05]

style nit: "public:" should be left-aligned and the functions four-space
indented.  See WebLayer below.

[qiankun, 2013/07/31 11:16:28]

Done.

+        virtual WebString debugName(WebLayer*) { return WebString(); }

[jamesr, 2013/07/30 17:37:40]

since this is going to be implemented inside Blink, make it pure virtual

[qiankun, 2013/07/31 11:16:28]

Done.

+
+    protected:
+        virtual ~WebLayerClient() { }
+};
 
 class WebLayer {
 public:
@@ -213,6 +221,8 @@ public:
 
     // True if the layer is not part of a tree attached to a WebLayerTreeView.
     virtual bool isOrphan() const = 0;
+
+    virtual void setWebLayerClient(WebKit::WebLayerClient*) = 0;

[jamesr, 2013/07/30 17:37:40]

Why is this a setter instead of being construction time?

[qiankun, 2013/07/31 11:16:28]

WebLayer's client may not exist when the Weblayer is created. Until
GraphicsLayer::setLinkHighlight() set m_linkHighlight and
GraphicsLayer::setupContentsLayer() set m_contentsLayer, we know the clients for
m_linkHighlight->layer() and m_contentsLayer. So, for such layers the setter is
required. 

 };
 
 } // namespace WebKit