Fix base_tx inefficiencies when modifying table in bundled mode.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78375880
Lower page bundle from 1024 to 512.
Serialize page payload into string for way better save/load performance
in Chrome.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78390281
Fixing PushDownSelectionsPass to work for more complex trees.

Specifically:
- Fixing pushDownNodeRec_() to push SelectNodes as down in the tree
as possible. Recursive calls were erroneously stopping early.
- Fixing pushDownValuePredNodeRec_() to allow ValuePredicate nodes to
propagate further down the tree.
- Modifying lf.tree.removeNode() to preserve the order of children when
removing a node that has child nodes.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78451862
Change code generation for row deserialization: avoid unnecessary copying
if the table contains no special column, which improve initial loading
speed.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78453336
Adding benchmark for opening connection to populated DB.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78460927
Stop increasing lf.Row.nextId unnecessarily.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78468035
Disable cross-column index for now. Will re-enable until we have an
implementation that yields correct results for all cases.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78468724
Optimize delete all execution to use more efficient IDBObjectStore.clear.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78599159
Add cross-browser benchmark results for browser vendors' references.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78630500