Use extent_commit_wrapper() rather than directly calling commit hook.
Use extent_commit_wrapper() rather than directly calling commit hook.

As a side effect this causes the extent's 'committed' flag to be
updated.

wqfish/jemalloc,glandium/jemalloc,wqfish/jemalloc,wqfish/jemalloc,8l/jemalloc,wqfish/jemalloc,glandium/jemalloc,8l/jemalloc,wqfish/jemalloc,glandium/jemalloc,8l/jemalloc,glandium/jemalloc,8l/jemalloc