Add OVERRIDE to printing/.

printing/printing_context_gtk.h

Index: printing/printing_context_gtk.h
diff --git a/printing/printing_context_gtk.h b/printing/printing_context_gtk.h
index 2dddd436c4a966d6ad4f4e665ea731697f547a2c..dbb89410db54a1516a03b1934f680bfacca98bf4 100644
--- a/printing/printing_context_gtk.h
+++ b/printing/printing_context_gtk.h
@@ -35,19 +35,19 @@ class PRINTING_EXPORT PrintingContextGtk : public PrintingContext {
   virtual void AskUserForSettings(gfx::NativeView parent_view,
                                   int max_pages,
                                   bool has_selection,
-                                  PrintSettingsCallback* callback);
-  virtual Result UseDefaultSettings();
+                                  PrintSettingsCallback* callback) OVERRIDE;
+  virtual Result UseDefaultSettings() OVERRIDE;
   virtual Result UpdatePrinterSettings(
       const base::DictionaryValue& job_settings,
-      const PageRanges& ranges);
-  virtual Result InitWithSettings(const PrintSettings& settings);
-  virtual Result NewDocument(const string16& document_name);
-  virtual Result NewPage();
-  virtual Result PageDone();
-  virtual Result DocumentDone();
-  virtual void Cancel();
-  virtual void ReleaseContext();
-  virtual gfx::NativeDrawingContext context() const;
+      const PageRanges& ranges) OVERRIDE;
+  virtual Result InitWithSettings(const PrintSettings& settings) OVERRIDE;
+  virtual Result NewDocument(const string16& document_name) OVERRIDE;
+  virtual Result NewPage() OVERRIDE;
+  virtual Result PageDone() OVERRIDE;
+  virtual Result DocumentDone() OVERRIDE;
+  virtual void Cancel() OVERRIDE;
+  virtual void ReleaseContext() OVERRIDE;
+  virtual gfx::NativeDrawingContext context() const OVERRIDE;
 
  private:
   string16 document_name_;