Auto-updating TODO comments authors.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=77459233
Enforcing unique/primary key constraints in Journal#insertOrReplace.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=77467537
Use goog.Promise in select_benchmark.js

This is so that the perf benchmark can run on IE and Firefox for Windows.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=77468533
Converting Constraint#getNullable to getNonNullable.

This is in preparation of enforcing not-nullable constraints.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=77603646
Enforcing NOT NULL constraint check.

Ensuring that Journal#{insert|insertOrReplace|update} are performing
not-nullable constraint checks and throw exception if needed.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=77619053
Make generated schema.js instantiate index objects only once.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=77629957
Performing all constraint checks in one pass.

Before this CL each constraint check required its own pass over the modified
rows. This was unnecessary and affected performance negatively. The new approach
is as follows:

For each affected row, modify the index data structures immediately. If a
"uniqueness" constraint violation occurs the index throws an exception,
therefore there is no need for checking uniqueness constraints before updating
the indices. The only constraint check that requires its own pass is the "not
nullable" constraint.

As a result of the new approach several public methods in ConstraintChecker are
not needed anymore.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=77702924