clang-format: Make emacs integration work with narrowed buffers.

Use (call-process region nil ...) instead of (point-min) so that the
call works in narrowed buffers.

Patch by Philipp Stephani, thank you!

git-svn-id: svn://svn.chromium.org/llvm-project/cfe/trunk/tools/clang-format@281203 0b72dbe1-c17f-4bc7-b9db-2b4152be0356
1 file changed