RendererGL: enable GL_DEBUG_OUTPUT on Debug builds The intent was already to enable it but without glEnable(GL_DEBUG_OUTPUT) the Linux NVIDIA driver doesn't output anything. BUG= Change-Id: Ia9a500c2e792ee7c4e2a7be60d478419eda617e1 Reviewed-on: https://chromium-review.googlesource.com/385278 Commit-Queue: Corentin Wallez <cwallez@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org>