Run as for instance
```
pkg/front_end/tool/fasta -Dbenchmark=true -Diterations=3 compile pkg/compiler/bin/dart2js.dart
```
This will set benchmarking to true, do 3 iterations and eventually print
the benchmarking data as json. That can then be pasted into the attempted
visualizer.
This is a first stab, and might be replaced by something else down the line.
Change-Id: I8cb3a6bcf8717adf089d25a0fb432cb0b286aaa6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/231441
Reviewed-by: Johnni Winther <johnniwinther@google.com>
Commit-Queue: Jens Johansen <jensj@google.com>
Jens Johansen
287ae321a2