Improve the error message when a variable is referenced in the externs.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=53046409
Automated g4 rollback of changelist 53046409.

*** Reason for rollback ***

Breakages

*** Original change description ***

Improve the error message when a variable is referenced in the externs.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=53051786
Add playbackRate methods to the YouTube iframe player externs.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=53062176
Automated g4 rollback of changelist 53051786.

*** Reason for rollback ***

Breakage fixed.

*** Original change description ***

Automated g4 rollback of changelist 53046409.

*** Reason for rollback ***

Breakages

*** Original change description ***

Improve the error message when a variable is referenced in the externs.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=53066916