printPage to return void instead of bool

public/web/WebPlugin.h

 /*
  * Copyright (C) 2009, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2014 Opera Software ASA. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 115 matching lines @@
     virtual bool isPrintScalingDisabled() { return false; }
     // Returns true on success and sets the out parameter to the print preset options for the document.
     virtual bool getPrintPresetOptionsFromDocument(WebPrintPresetOptions*) { return false; }
 
     // Sets up printing with the specified printParams. Returns the number of
     // pages to be printed at these settings.
     virtual int printBegin(const WebPrintParams& printParams) { return 0; }
 
     // Prints the page specified by pageNumber (0-based index) into the supplied canvas.
     virtual bool printPage(int pageNumber, WebCanvas* canvas) { return false; }
+    // TODO: Remove third parameter when both blink and chromium changes land for bug496765
+    virtual void printPage(int pageNumber, WebCanvas* canvas, bool unused) { }
+
     // Ends the print operation.
     virtual void printEnd() { }
 
     virtual bool hasSelection() const { return false; }
     virtual WebString selectionAsText() const { return WebString(); }
     virtual WebString selectionAsMarkup() const { return WebString(); }
 
     virtual bool executeEditCommand(const WebString& name) { return false; }
     virtual bool executeEditCommand(const WebString& name, const WebString& value) { return false; }
 
@@ skipping 37 matching lines @@
     virtual bool isPlaceholder() { return true; }
     virtual bool shouldPersist() const { return false; }
 
 protected:
     ~WebPlugin() { }
 };
 
 } // namespace blink
 
 #endif