Fix doubly defined variables in libANGLE and libGLESv2. We can get by with only including these in libANGLE, since libGLESv2 pulls in libANGLE. BUG=angle:773 Change-Id: Iccbdb968b3c55528e2a7e1dd55f4f1280a70bfe9 Reviewed-on: https://chromium-review.googlesource.com/232967 Tested-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Brandon Jones <bajones@chromium.org>