Roll engine ce6ab8ce25fa..a206557f8fb8 (5 commits) (#41440)

git@github.com:flutter/engine.git/compare/ce6ab8ce25fa...a206557f8fb8

git log ce6ab8ce25fa..a206557f8fb8 --no-merges --oneline
2019-09-27 skia-flutter-autoroll@skia.org Roll src/third_party/skia ec85f407bfee..b83cc76a5e3a (15 commits) (flutter/engine#12472)
2019-09-27 30870216+gaaclarke@users.noreply.github.com Added a default entrypoint variable to match android syntax. (flutter/engine#12370)
2019-09-26 tauu@h2overclock.de [web_ui] add missing dispose handler for MethodCalls to flutter/platform_view (flutter/engine#12226)
2019-09-26 tauu@h2overclock.de [web_ui] PersistedPlatformView attribute update handling to enable resizing (flutter/engine#12227)
2019-09-26 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from z3PaM... to HoRV8... (flutter/engine#12471)


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 aaclarke@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

-ce6ab8ce25fa4d06c27a8043b7be2a970f133d21
+a206557f8fb8a957d145f0123e2d72403b403a80