Roll Flutter Engine from 2ec0f74a1e8a to b11e318b3690 (2 revisions) (#137785)

https://github.com/flutter/engine/compare/2ec0f74a1e8a...b11e318b3690

2023-11-02 skia-flutter-autoroll@skia.org Roll Skia from 70634da5c783 to 2b3472da9888 (5 revisions) (flutter/engine#47608)
2023-11-02 jonahwilliams@google.com [Impeller] add support for specialization constants. (flutter/engine#47432)

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 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

-2ec0f74a1e8ad0175f3bd526371ae62c95086f60
+b11e318b36902be2cfceba7577631b421092ce51