Fix annotation equivalence for Keys in Dagger 2.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=69332953
Merge pull request #28 from google/moe_writing_branch_from_8fd8d27cb2d58b7f106a5a7990d8431a49cd690d

Fix annotation equivalence for Keys in Dagger 2.