Not for review - Rebase of crrev.com/62833003

public/web/WebViewClient.h

Index: public/web/WebViewClient.h
diff --git a/public/web/WebViewClient.h b/public/web/WebViewClient.h
index 9e7b1a3f902ddaa7e0a25519cd6316fae51bf7d1..85dec24aa3157e1a6130d01f04a93d7a601afd74 100644
--- a/public/web/WebViewClient.h
+++ b/public/web/WebViewClient.h
@@ -99,7 +99,10 @@ public:
         return 0;
     }
 
-    // Create a new WebPopupMenu.
+    virtual size_t compositorId() const { return 0; }
+
+    // Create a new WebPopupMenu. In the second form, the client is
+    // responsible for rendering the contents of the popup menu.
     virtual WebWidget* createPopupMenu(WebPopupType) { return 0; }
     virtual WebWidget* createPopupMenu(const WebPopupMenuInfo&) { return 0; }