ReceiveCommits: Sort list of updated changes in output

Previously, the updated changes were reported to the client in
arbitrary HashMap iteration order. (This was not the case with new
changes, which are already created in-order in a list.)

Change-Id: I5d6dd148769fc87878854f35f1137772986b95ea
ChangeNotesTest: Add missing @Test annotation

Change-Id: I794dc288b00eb10c2bbfed47bf52b4bd793db872
Remove unused insert method from secondary index interface

The `insert` method is not used anywhere.  The `replace` method is
used instead.

Change-Id: Ie47253149cacde9a0824e4dee4d80313acd33188
Merge "ChangeNotesTest: Add missing @Test annotation"
ChangeRebuilder: Remove unused GitRepositoryManager

Change-Id: I140005adef6260f08e219b9959725f0d958b3e44