Added missing chrome.tabs.onReplaced extern.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=54199598
Remove trailing space.

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Created by MOE: http://code.google.com/p/moe-java
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=54239147
Remove incorrect @override declaration on MessageEvent.prototype.initMessageEvent.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=54602128
Add DOM traversal interface to javascript externs -- adds createNodeIterator and createTreeWalker.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=54682338