Remove SPAC restriction on non-unique index persistence.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81603219
Create backstore tables corresponding to RowId index.

Also ensure that the persisted metadata for such tables has the correct
index type "rowid".
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81605260
Instantiating BTree indices from MemoryIndexStore when index is persisted.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81616387
Fixing Btree#testRandomNumbers to use integers as values.

This is most likely related to the observed flakiness on Firefox.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81620237
Turn lf.schema.Table from an interface into a class.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81628035