Remove Hack used in blink side for merging dependent chromium and blink patches.

public/web/WebWidgetClient.h

Index: public/web/WebWidgetClient.h
diff --git a/public/web/WebWidgetClient.h b/public/web/WebWidgetClient.h
index 215fa23f61539784f828c581e47299170461fb69..5a18e0f0367e6abec32f715986a66534335eadff 100644
--- a/public/web/WebWidgetClient.h
+++ b/public/web/WebWidgetClient.h
@@ -59,13 +59,7 @@ public:
     virtual void didAutoResize(const WebSize& newSize) { }
 
     // Called when the compositor is enabled or disabled.
-    // The parameter to didActivateCompositor() is meaningless.
-    // FIXME: The older definiton of didActivateCompositor (i.e with arguments)
-    // and all its corresponding call is to removed once the dependent chromium
-    // side patch https://codereview.chromium.org/137893025/ lands and all overrides
-    // of older definition are removed from chromium side.
     virtual void didActivateCompositor() { }
-    virtual void didActivateCompositor(int deprecated) { }
     virtual void didDeactivateCompositor() { }
 
     // Attempt to initialize compositing for this widget. If this is successful,