commit 2b2f3897cf96964f5ef612d98b7cfe8fb7f452f8
author Edwin Kempin <ekempin@google.com> Fri Jan 25 10:34:07 2019 +0100
committer Edwin Kempin <ekempin@google.com> Tue Jan 29 08:54:42 2019 +0100
tree 21d265fda8f427fdd72c955df8f3a99f3795af77
parent b746dadf3ee9c6d23681734c9215d513156f4426

Support searching changes which only touch certain file extensions

With the current 'extension' search operator it's possible to find
a) changes that contain at least one file with the given extension,
   e.g.: extension:txt
b) changes that contain no file with the given extension,
   e.g.: -extension:txt

However sometimes you want to match changes which only contain files of
a given extension, e.g. changes that only touch txt files. This can now
be done with the new 'only_extensions' search operator, e.g.:
  only_extensions:txt

It is also possible to specify multiple file extensions. E.g. matching
changes that only touch txt and jpg files can be done by:
  only_extensions:jpg,txt

By reversing the 'only_extensions' search operator it is possible to
match changes that not only touch files with certain extensions, e.g.:
  -only_extensions:jpg,txt

The order and the case in which the extensions are provided to the
'only_extensions' operator don't matter.

Also extensions can be specified with or without leading '.' (same as
for the 'extension' search operator).

Changes that contain files without file extension can be matched by
including an empty file extension into the file extension list, e.g.:
* changes that only include txt files and files without extension:
  only_extensions:,txt
* changes that only contain files without extension:
  only_extensions:,
  only_extensions:""

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I3d2b978ed455f835d1dad2daa920be0b0ec2ae36