Exposing "GL_APPLE_texture_format_BGRA8888" fully enables BGRA8 in
Chromium and it seems like SwiftShader isn't properly supporting it
yet, so removing the string for now in order to do the DEPS roll.

Change-Id: I72f57899b820c22ac76a59b0b7a5e3d2a920e2b3
Reviewed-on: https://swiftshader-review.googlesource.com/16268Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>