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Summary: Search for D1234 currently finds everything but revision 1234.

Test Plan:
Search for:

• rX
• rX1234 under SVN
• rXabcd under GIT
• D1234
• T4

Reviewers: epriestley

Reviewed By: epriestley

CC: aran

Differential Revision: https://secure.phabricator.com/D2081