Resize images for hi-dpi based on a custom PNG chunk added by GRIT r78, and roll GRIT r78

ui/gfx/image/image_skia.h

Index: ui/gfx/image/image_skia.h
diff --git a/ui/gfx/image/image_skia.h b/ui/gfx/image/image_skia.h
index 2dfc131181dd0e215058e4180d88e0dbe371ed87..5221e31f455b09f56db0d64caaebe2ee65f3e9d8 100644
--- a/ui/gfx/image/image_skia.h
+++ b/ui/gfx/image/image_skia.h
@@ -45,6 +45,11 @@ class UI_EXPORT ImageSkia {
   // ImageSkia owns |source|.
   ImageSkia(ImageSkiaSource* source, const gfx::Size& size);
 
+  // Creates an instance that uses the |source|. The constructor loads the image
+  // at |scale_factor| and uses its dimensions to calculate the size in DIP.
+  // ImageSkia owns |source|.
+  ImageSkia(ImageSkiaSource* source, ui::ScaleFactor scale_factor);
+
   // Adds ref to passed in bitmap.
   // DIP width and height are set based on scale factor of 1x.
   // TODO(pkotwicz): This is temporary till conversion to gfx::ImageSkia is