Fix gfx::Canvas::DrawStringRectWithHalo

ui/gfx/canvas.h

Index: ui/gfx/canvas.h
diff --git a/ui/gfx/canvas.h b/ui/gfx/canvas.h
index 311cf38830cac30cb1c455827d542ec853aaab41..b76871cdb81c72298e143b5bbd7d6a1570764a78 100644
--- a/ui/gfx/canvas.h
+++ b/ui/gfx/canvas.h
@@ -72,6 +72,9 @@ class GFX_EXPORT Canvas {
     // when rendering text onto a fully- or partially-transparent background
     // that will later be blended with another image.
     NO_SUBPIXEL_RENDERING = 1 << 9,
+
+    // Draw text with 1px border.
+    HALO_EFFECT = 1 << 10,
   };
 
   // Creates an empty canvas with image_scale of 1x.