These entry points are part of EGL_EXT_platform_base but were never returned by
eglGetProcAddress.

BUG=angleproject:2603

Change-Id: I4782df67fa8625a9af29a18df02af7b5fa73d75e
Reviewed-on: https://chromium-review.googlesource.com/1075469Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Geoff Lang <geofflang@chromium.org>