GLES2: Apply clang-format to entry points. This will make the diff for the auto-gen patch easier to review. BUG=angleproject:1309 Change-Id: I58526a29b7f538b45409c6ab48b75b41b3521321 Reviewed-on: https://chromium-review.googlesource.com/487883 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Corentin Wallez <cwallez@chromium.org>