Roll engine a05803a..0b6aa5e (2 commits) (flutter#42443)

git@github.com:flutter/engine.git/compare/a05803a0d2ba...0b6aa5e

git log a05803a..0b6aa5e --no-merges --oneline
2019-10-10 yjbanov@google.com Add "felt clean" command (flutter/engine#13042)
2019-10-10 skia-flutter-autoroll@skia.org Roll src/third_party/skia 0fc9b3829b47..69537d798994 (1 commits) (flutter/engine#13061)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC chinmaygarde@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

bin/internal/engine.version

@@ -1 +1 @@
-a05803a0d2baaadedb8dd4385c72b0c75c040341
+0b6aa5e3201ad2fc5989ecf6740078537d32a262