From a performance perspective, this change to `enumerateDeltasUsingBlock ` is a big improvement - the old code created the `git_diff_patch` (now renamed `git_patch`) and grabbed the `git_diff_delta` from it which was actually performing the entire text diff just to extra the file-to-file metadata. This new way, the deltas can be enumerated without actually loading and processing the file contents. This call goes from being quite expensive to being virtually no overhead.

That being said, there is a minor behavior change as a result - the binary file detection on the deltas will no longer be completely accurate since this new version will not load the file content. If a file is marked binary by git attributes, it will be correctly noted, but the file content will no longer be examined for NUL bytes.