GL: Avoid infinite loops clearing GL errors When a GL_CONTEXT_LOST error is generated, every subsequent call to glGetError will also return GL_CONTEXT_LOST. Avoid this by early returning. The error will be picked up later by the HandleError call. Bug: chromium:368263759 Change-Id: I132e3ecaf240e90f26060e1188736a3374bf88dc Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5887225 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Geoff Lang <geofflang@chromium.org>