Don't expose detailed driver version info to webGL WebGL's GL_RENDERER string now only includes basic version information on all backends. This is controlled through a bool passed through getBackendVersionString. Bug: angleproject:6777 Change-Id: Ie4e3d91d22c96f175a8139fac1c66e985ed9e1b7 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3380263 Reviewed-by: Jonah Ryan-Davis <jonahr@google.com> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Sean Risser <srisser@google.com>