Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

class-extension-protocol.m
// RUN: rm -rf %t.cache
// RUN: %clang_cc1 %s -fsyntax-only -fmodules -fimplicit-module-maps -fmodules-cache-path=%t.cache -I%S/Inputs/class-extension -verify
// expected-no-diagnostics

#import "a-private.h"

int foo(A *X) {
  return X.p0 + X.p1;
}