WebView context menu cleanup.

extensions/browser/extensions_browser_client.h

Index: extensions/browser/extensions_browser_client.h
diff --git a/extensions/browser/extensions_browser_client.h b/extensions/browser/extensions_browser_client.h
index 269dc8ea6bc411dc0730e9003083ac5a39eb0d75..4aefa37e7ad8759f3364511488ca206965b96334 100644
--- a/extensions/browser/extensions_browser_client.h
+++ b/extensions/browser/extensions_browser_client.h
@@ -222,6 +222,10 @@ class ExtensionsBrowserClient {
   virtual ExtensionWebContentsObserver* GetExtensionWebContentsObserver(
       content::WebContents* web_contents) = 0;
 
+  // Cleans up browser-side state associated with a WebView that is being
+  // destroyed.
+  virtual void CleanUpWebView(int embedder_process_id, int view_instance_id) {}
+
   // Returns the single instance of |this|.
   static ExtensionsBrowserClient* Get();