find_headers.py to better find headers.

The find_headers.py script claims to "recursively search each include
directory for headers" but the recursive part has been left out.

This changes find_headers to instead find all the sources which are in
public include directories and list them with the shortest possible
path. This removes the need for a blacklist and also handles includes in
subdirectories of public include directories.

Change-Id: Ib59256a2059d37d4459686c421923207ac7acf38
Reviewed-on: https://skia-review.googlesource.com/129660
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
3 files changed