Roll Flutter Engine from 913446eca57c to a3f9393f9591 (2 revisions) (#140144)

https://github.com/flutter/engine/compare/913446eca57c...a3f9393f9591

2023-12-14 skia-flutter-autoroll@skia.org Roll Skia from 6c2b3d8cecf1 to 47f84c5cf15d (1 revision) (flutter/engine#49020)
2023-12-14 skia-flutter-autoroll@skia.org Roll Skia from 89ecb7c9cd2a to 6c2b3d8cecf1 (1 revision) (flutter/engine#49017)

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 jsimmons@google.com,rmistry@google.com,zra@google.com on the revert to ensure that a human
is aware of the problem.

To file a bug in Flutter: https://github.com/flutter/flutter/issues/new/choose

To report a problem with the AutoRoller itself, please file a bug:
https://issues.skia.org/issues/new?component=1389291&template=1850622

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

bin/internal/engine.version

-913446eca57c988d9426de18c1bb36195deb122b
+a3f9393f959181df6b61d06ef126f4b8787ba70d