Fix scrollbar buttons at hidpi when enable-use-zoom-for-dsf is on.

content/child/webthemeengine_impl_default.h

Index: content/child/webthemeengine_impl_default.h
diff --git a/content/child/webthemeengine_impl_default.h b/content/child/webthemeengine_impl_default.h
index c927e5a6099ce9223157f96ea6c3386e9177a5c0..e4e1c7eaddc2f167e028aeab3ecfdbde5c65c4f9 100644
--- a/content/child/webthemeengine_impl_default.h
+++ b/content/child/webthemeengine_impl_default.h
@@ -27,14 +27,6 @@ class WebThemeEngineImpl : public blink::WebThemeEngine {
                                     blink::WebThemeEngine::State endState,
                                     double progress,
                                     const blink::WebRect& rect);
-
-#if defined(OS_WIN)
-  // Caches the scrollbar metrics.
-  static void cacheScrollBarMetrics(int32_t vertical_scroll_bar_width,
-                                    int32_t horizontal_scroll_bar_height,
-                                    int32_t vertical_arrow_bitmap_height,
-                                    int32_t horizontal_arrow_bitmap_width);
-#endif
 };
 
 }  // namespace content