Roll engine 2bce4ed87a48..6f7700fc8382 (4 commits) (#35202)

https://github.com/flutter/engine/compare/2bce4ed87a48...6f7700fc8382

git log 2bce4ed87a48d3434ff19a39b1b70b5a94436d19..6f7700fc83827ef8adbd0966ed369a6cab549d9c --no-merges --oneline
6f7700fc8 fix FlutterOverlayView doesn't remove from superview in some cases (flutter/engine#9532)
f3cc37552 Roll fuchsia/sdk/core/mac-amd64 from XT8hP4vbTcjWCQU7H_kwgDtIt2lXCWVgJkMNU252lZ8C to dcGnduqJ5C8ozmUHeeboHC76nOv7s4XfCKIfefQlGkQC (flutter/engine#9538)
bc85f7302 Roll fuchsia/sdk/core/linux-amd64 from L_ORUWXyDEC29pSiSyKIwGqcFMQFsV91E3h_wPbUIUkC to SuKWYMSXAMq1uTo9eaIdIOQqBb7Ro-zLyNk01GPOiU8C (flutter/engine#9537)
bf3a3106c Roll fuchsia/sdk/core/mac-amd64 from Emw56Db0zg6Cnvgo7myIDZX0Lq-A6DFwEJHiPnr8K38C to XT8hP4vbTcjWCQU7H_kwgDtIt2lXCWVgJkMNU252lZ8C (flutter/engine#9531)

The AutoRoll server is located here: https://autoroll.skia.org/r/flutter-engine-flutter-autoroll

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

If the roll is causing failures, please contact the current sheriff (chinmaygarde@google.com), and stop
the roller if necessary.

bin/internal/engine.version

-2bce4ed87a48d3434ff19a39b1b70b5a94436d19
+6f7700fc83827ef8adbd0966ed369a6cab549d9c