Revert "Revert "Revert "replace SkXfermode obj with SkBlendMode enum in paints"""

This reverts commit I86875511a13497112827cbaed1dbd7639e9e3d10.

legacy (100K) skp failure

Original change's description:
> Revert "Revert "replace SkXfermode obj with SkBlendMode enum in paints""
> 
> This reverts commit ce02e7175872abde3721df9e5d3ec0ab8384cd8e.
> 
> BUG=skia:
> 
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2878
> 
> Change-Id: I86875511a13497112827cbaed1dbd7639e9e3d10
> Reviewed-on: https://skia-review.googlesource.com/2878
> Reviewed-by: Matt Sarett <msarett@google.com>
> Commit-Queue: Mike Reed <reed@google.com>
> 

TBR=msarett@google.com,reed@google.com,reviews@skia.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: Ife6f0cf3a22b3e8cf885a188f7f44e1ff62e06a5
Reviewed-on: https://skia-review.googlesource.com/2881
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
139 files changed