Do not convert from RectF to Rect by flooring.

ui/gfx/image/image_skia_operations.cc

Index: ui/gfx/image/image_skia_operations.cc
diff --git a/ui/gfx/image/image_skia_operations.cc b/ui/gfx/image/image_skia_operations.cc
index a9809b38f3a7dc4847992895b1666f352e00224a..122795d054471c2c2b4452eaa2f2a61f2817db92 100644
--- a/ui/gfx/image/image_skia_operations.cc
+++ b/ui/gfx/image/image_skia_operations.cc
@@ -286,8 +286,9 @@ class ExtractSubsetImageSource: public gfx::ImageSkiaSource {
   // gfx::ImageSkiaSource overrides:
   virtual ImageSkiaRep GetImageForScale(ui::ScaleFactor scale_factor) OVERRIDE {
     ImageSkiaRep image_rep = image_.GetRepresentation(scale_factor);
-    SkIRect subset_bounds_in_pixel = RectToSkIRect(subset_bounds_.Scale(
-        ui::GetScaleFactorScale(image_rep.scale_factor())));
+    SkIRect subset_bounds_in_pixel = RectToSkIRect(
+        subset_bounds_.ScaleUnsafe(
+            ui::GetScaleFactorScale(image_rep.scale_factor())));
     SkBitmap dst;
     bool success = image_rep.sk_bitmap().extractSubset(&dst,
                                                        subset_bounds_in_pixel);