[vm] Distinguish between C and Dart frame layouts in the profiler's stack walker.
[vm] Distinguish between C and Dart frame layouts in the profiler's stack walker.

This can differ in simulator builds.

TEST=stack traces on assertion failures in simriscv64
Bug: https://github.com/dart-lang/sdk/issues/38587
Change-Id: Ib5aae0f2b7af2bf64fc4ae0f1dddadea6670a88d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/227381
Reviewed-by: Ben Konyi <67ffcaedcc3dc3d87dddb9627b72dd41756b31b1@google.com>
Commit-Queue: Ryan Macnak <d738b7f001baf9789095d7dc549cff6de60b011d@google.com>

dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk