With https://chromium.googlesource.com/skia/+/43b8b36b20ae00e2d78421c4cda1f3f922983a20 blink_perf.layout regressed. It appears that the typeface cache is being missed. This is a partial revert of the Skia change which reverts the smallest amount of code to restore performance.

BUG=chromium:425566

Committed: https://skia.googlesource.com/skia/+/47eda52e8fb88f0725b401762a3e0bddc98e9fb3

Review URL: https://codereview.chromium.org/693213002
Rebase verttext once more

TBR=jvanverth@google.com

BUG=skia:

Review URL: https://codereview.chromium.org/717553002
Address MSAA rendering in layer hoisting

This became relevant whilst attempting to rebaseline the multipicturedraw GMs after turning on layer hoisting inside Skia.

Review URL: https://codereview.chromium.org/709943003
Update some flaky GMs to see if they stick.

TBR=jcgregorio@google.com

Review URL: https://codereview.chromium.org/713893002
Small refactoring of layer discovery code

This CL removes CollectLayers' reliance on having the top most picture (by removing the unused fPictureID member). This then allows making CollectLayers' API closer to that of SkRecordFillBounds in order to facilitate using them interchangeably.

Review URL: https://codereview.chromium.org/714533002
flag imageinfo as srgb

intended uses:
- flag a SkSurface as sRGB (only supported by Ganesh for now)
- flag images (e.g. png or jpeg) as sRGB if the codec tells us that

wins:
- faster gamma-correct text (esp. w/ distance-fields) when we can use sRGB for text
- better color fidelity when the screen really is sRGB

Review URL: https://codereview.chromium.org/676883003