Don't retain strings in the debugLog by default.

You can turn the debug log back on by switching CompilerOptions.useDebugLog to true.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65405798
[NEW TYPE INFERENCE] Don't crash on getprop of BOTTOM
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65407612
[NEW TYPE INFERENCE] Don't crash in creating deferred checks.

If specialize can remove functions, then any property access can remove
a function.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65455150
Always use the debug log when running determinism checks.
(It is a prerequisite).
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65460619
[NEW TYPE INFERENCE] Handle @suppress annotations.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65464782
[NEW TYPE INFERENCE] Don't crash inside prototype methods of undefined classes.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65472746
Fix error format string so that it gets printed properly (e.g. "Don't know how to handle CLASS" instead of "Dont know how to handle {0}"
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65474956
Use fewer HashSets in closure compiler.  Use EnumSets or ImmutableSets where possible.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65475898
Upgrade to Guava 17.0
- https://code.google.com/p/guava-libraries/wiki/Release17
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65477726