Replace getBaseLayerSize() with the size passed to DrawingRecorder.

third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.cpp

Index: third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.cpp
diff --git a/third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.cpp b/third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.cpp
index a8c226868f1d8ffb2bd2282ee5f13bfea8c86840..b978eecd5211803858547d78baee97e6b730dabc 100644
--- a/third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.cpp
+++ b/third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.cpp
@@ -209,7 +209,7 @@ void ScrollbarThemeOverlay::PaintThumb(GraphicsContext& context,
   // Horizontally flip the canvas if it is left vertical scrollbar.
   if (scrollbar.IsLeftSideVerticalScrollbar()) {
     canvas->save();
-    canvas->translate(canvas->getBaseLayerSize().width(), 0);
+    canvas->translate(rect.Width(), 0);
     canvas->scale(-1, 1);
   }