Roll engine 3a445edda924..5b3182294f63 (3 commits) (#42258)

git@github.com:flutter/engine.git/compare/3a445edda924...5b3182294f63

git log 3a445edda924..5b3182294f63 --no-merges --oneline
2019-10-08 bkonyi@google.com Roll src/third_party/dart aece1c1e92..f4a72bfc64 (4 commits)
2019-10-08 30870216+gaaclarke@users.noreply.github.com Added an embedder example (flutter/engine#12808)
2019-10-08 sebastian.roth@gmail.com Fix typo on channel buffer debug output. (flutter/engine#12960)


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

-3a445edda924add8cd7e22ffa1a20d198ae0e7e3
+5b3182294f6369bbb2b850d43dbb6710c64ca5b2