Reland of Move scaling of ui resources for scrollbars to the time of upload

cc/layers/painted_scrollbar_layer.h

Index: cc/layers/painted_scrollbar_layer.h
diff --git a/cc/layers/painted_scrollbar_layer.h b/cc/layers/painted_scrollbar_layer.h
index ef0f2e87fad3ff04dcd909157a0b0dd5f143cc59..89133a682404c37a7d90fdf1aaefa455cb9427a6 100644
--- a/cc/layers/painted_scrollbar_layer.h
+++ b/cc/layers/painted_scrollbar_layer.h
@@ -72,9 +72,6 @@
     return true;
   }
 
-  int MaxTextureSize();
-  float ClampScaleToMaxTextureSize(float scale);
-
   UIResourceBitmap RasterizeScrollbarPart(const gfx::Rect& layer_rect,
                                           const gfx::Rect& content_rect,
                                           ScrollbarPart part);