Add instruction count to the top of SkRP dumps.

At one point, the instruction count was 1:1 with the number of lines
in the dump, but labels and immutable data cost zero instructions,
so having an explicit count can be beneficial.

Change-Id: I556912e8080b81bcf246c98e37891cd22700487d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/726256
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
244 files changed