Users were seeing different behavior when querying GL_INFO_LOG_LENGTH
with ANGLE because ANGLE was always adding a newline to the InfoLog.

Bug: chromium:1191293
Change-Id: I50f56326871cdd2f6614f5b1622257845721244c
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2795164
Commit-Queue: Jonah Ryan-Davis <jonahr@google.com>
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>