use the right NativeTheme on bubbles + dialogs on Aura Linux

ui/views/linux_ui/linux_ui.h

Index: ui/views/linux_ui/linux_ui.h
diff --git a/ui/views/linux_ui/linux_ui.h b/ui/views/linux_ui/linux_ui.h
index cadc7b72632b51f0806acff2cb51c3e7621dd637..f576234b5dbf5451987ed773bb84a7613827499f 100644
--- a/ui/views/linux_ui/linux_ui.h
+++ b/ui/views/linux_ui/linux_ui.h
@@ -19,6 +19,10 @@
 // The main entrypoint into Linux toolkit specific code. GTK code should only
 // be executed behind this interface.
 
+namespace aura {
+class Window;
+}
+
 namespace gfx {
 class Image;
 }
@@ -87,7 +91,7 @@ class VIEWS_EXPORT LinuxUI : public ui::LinuxInputMethodContextFactory,
 
   // Returns a NativeTheme that will provide system colors and draw system
   // style widgets.
-  virtual ui::NativeTheme* GetNativeTheme() const = 0;
+  virtual ui::NativeTheme* GetNativeTheme(aura::Window* window) const = 0;
 
   // Returns whether we should be using the native theme provided by this
   // object by default.