Deprecate the platform-theme-changed event

atom/browser/api/atom_api_app.h

@@ -92,10 +92,6 @@ class App : public AtomBrowserClient::Delegate,
   // content::GpuDataManagerObserver:
   void OnGpuProcessCrashed(base::TerminationStatus exit_code) override;
 
-#if defined(OS_MACOSX)
-  void OnPlatformThemeChanged() override;
-#endif
-
  private:
   // Get/Set the pre-defined path in PathService.
   base::FilePath GetPath(mate::Arguments* args, const std::string& name);