Revert 224473 "Remove dependency on ui::ScaleFactor from ui/gfx"

Revert 224473 "Remove dependency on ui::ScaleFactor from ui/gfx"

> Remove dependency on ui::ScaleFactor from ui/gfx
> 
> As part of the work to removed dependencies on ui/base from ui/gfx I have
> changed the public api to Canvas, ImageSkia, ImageSkiaRep and ImagePNGRep
> to take float scale values instead of ui::ScaleFactor.
> 
> The notion of supported scale factors has been broken into 2 parts.
> ui::SetSupportedScaleFactors remains and calls the
> new ImageSkia::SetSupportedScales().
> 
> The initialization of the supported scale factors has been moved from layout.h
> into ResourceBundle, and is done explicitly in tests that don't use
> ResourceBundle.
> 
> BUG=103304
> R=ben@chromium.org, oshima@chromium.org, sky@chromium.org
> 
> Review URL: https://codereview.chromium.org/24175004

TBR=davemoore@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=224499

[DaveMoore, 2013-09-20 21:54:57]

Committed patchset #1 manually as r224499.