Added varying struct

TBR=
BUG=skia:

Committed: https://skia.googlesource.com/skia/+/852ae80b9c3c6fd53f993ac35133d80863993cbe

Review URL: https://codereview.chromium.org/671023002
tools: Remove reference to svndiff.

svndiff script was archived by commit
https://skia.googlesource.com/skia/+/70242ace3b2ed06b33ee5ea5c9ac3aedea89b194

R=borenet@google.com

Review URL: https://codereview.chromium.org/658923002
Add some more volatile paths.

Some clip paths were not marked as volatile, and ending up in the
distance field path renderer when they shouldn't.

BUG=skia:3066

Review URL: https://codereview.chromium.org/680543002
When bmp is not cached don't upload as index8 format.

Review URL: https://codereview.chromium.org/673883002
Delete unused method aliases and texture flag.

Committed: https://skia.googlesource.com/skia/+/7fdffe41494cbd78a8ee2a6ef0509e46ec77039f

Review URL: https://codereview.chromium.org/672753002
Doing the "using namespace" penance by adding in v8:: everywhere, like I should have to begin with.

Also:
  - SkWindow now has createSurface, not createCanvas.
  - Add the platform init code v8 now seems to require.
  - Fix library linkage.
  - Call isolate->Enter(); because it doesn't look
    like v8 starts with a default isolate to begin with.

BUG=skia:

Review URL: https://codereview.chromium.org/673223002
Update GM expectations for https://codereview.chromium.org/677463002/

BUG=skia:2935
TBR=mtklein@google.com

Review URL: https://codereview.chromium.org/677123002
Add `SkIRect bounds()` convenience method to SkImageInfo and SkBitmap.

Review URL: https://codereview.chromium.org/646213003