ee722302b3
The index field has always been stored lowercase, since we intended
hashtag searches to be case-insensitive. However, we never converted the
input string to lower case, with the unexpected result that searching
for [hashtag:ACamelCaseTag] would not return results for changes who
contain that exact hashtag.
Bug: Issue 10564
Change-Id: I86019d18fd0d183d857d5a91d2af20d3445c6c25
(cherry picked from commit c8d1c47f1f)