Merge branch 'rs/xdiff-hunk-with-func-line'

"git show -W" (extend hunks to cover the entire function, delimited by lines that match the "funcname" pattern) used to show the entire file when a change added an entire function at the end of the file, which has been fixed. * rs/xdiff-hunk-with-func-line: xdiff: fix merging of appended hunk with -W grep: -W: don't extend context to trailing empty lines t7810: add test for grep -W and trailing empty context lines xdiff: don't trim common tail with -W xdiff: -W: don't include common trailing empty lines in context xdiff: ignore empty lines before added functions with -W xdiff: handle appended chunks better with -W xdiff: factor out match_func_rec() t4051: rewrite, add more tests