Add always-on-top property to app windows

chrome/browser/extensions/api/app_current_window_internal/app_current_window_internal_api.h

Index: chrome/browser/extensions/api/app_current_window_internal/app_current_window_internal_api.h
diff --git a/chrome/browser/extensions/api/app_current_window_internal/app_current_window_internal_api.h b/chrome/browser/extensions/api/app_current_window_internal/app_current_window_internal_api.h
index 0bf5c4ac3d0a9b653e886afc554cae5b90f5c167..648724f1e5e508ce6bc6e17b770447c2237dd89e 100644
--- a/chrome/browser/extensions/api/app_current_window_internal/app_current_window_internal_api.h
+++ b/chrome/browser/extensions/api/app_current_window_internal/app_current_window_internal_api.h
@@ -155,6 +155,17 @@ class AppCurrentWindowInternalSetInputRegionFunction
   virtual bool RunWithWindow(apps::ShellWindow* window) OVERRIDE;
 };
 
+class AppCurrentWindowInternalSetAlwaysOnTopFunction
+    : public AppCurrentWindowInternalExtensionFunction {
+ public:
+  DECLARE_EXTENSION_FUNCTION("app.currentWindowInternal.setAlwaysOnTop",
+                             APP_CURRENTWINDOWINTERNAL_SETALWAYSONTOP)
+
+ protected:
+  virtual ~AppCurrentWindowInternalSetAlwaysOnTopFunction() {}
+  virtual bool RunWithWindow(apps::ShellWindow* window) OVERRIDE;
+};
+
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_APP_CURRENT_WINDOW_INTERNAL_APP_CURRENT_WINDOW_INTERNAL_API_H_