Recognize larger regions of no-op control flow. Ideally we would be able to remove these regions from the CFG. Until then, pattern matching larger regions leaves fewer ghost conditions in the generated code.
With pattern matching, we are seeing more examples where this is necessary.
Bug: #29475
Change-Id: Ib0981400883631f56940288f8a32fbc5f3985dfb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/340067
Reviewed-by: Sigmund Cherem <sigmund@google.com>
Commit-Queue: Stephen Adams <sra@google.com>
Stephen Adams