Fix ContextLostTest if robustness ext is disabled Reset notification behavior is defined in the GL_EXT_robustness extension, and the resulting context must support the extension and the specified reset strategy. So if the ext is not supported, it should disable delivery of reset notifications. Bug: angleproject:4823 Change-Id: I49b9364a83eab9ebc0fdca3b1dc075c1a43070cf Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2302874 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>