Added stubs for these soon to be added extensions: - GL_OES_depth_texture_cube_map - GL_EXT_read_format_bgra - GL_NV_depth_buffer_float2 - GL_NV_read_depth - GL_NV_read_stencil Bug: angleproject:4293 Bug: angleproject:4294 Bug: angleproject:4295 Change-Id: I56cf1fda377e48521f30bd11f5776409bfb88701 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2001480 Commit-Queue: Alexis Hétu <sugoi@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>
