Revert "Revert "GrContext::dump that produces JSON formatted output""

This reverts commit 0f450acd76fd58a2f7464f99869ed6afbfac303c.

Bug: skia:
Change-Id: I97428fbbc6d82bf8b186ec5fdbf1a939c00e4126
Reviewed-on: https://skia-review.googlesource.com/32726
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
20 files changed