Trace Tests: Add renderer string logging.
Trace Tests: Add renderer string logging.

This outputs the GL_RENDERER string in each test when using the
--verbose-logging command-line flag.

Bug: b/173518650
Change-Id: Id966294d50aaba0c8a1f3e010f76d5560e6f1288
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2545403
Reviewed-by: Charlie Lao <2661ca4ca24c371418789adbc76dfb4875087223@google.com>
Reviewed-by: Courtney Goeltzenleuchter <aa371ec5c940a0ded89f7ed95bce84faebcf51df@google.com>
Commit-Queue: Jamie Madill <7e492b4f1c8458024932de3ba475cbf015424c30@chromium.org>

ppy/angle,ppy/angle,ppy/angle,ppy/angle