Add an optional type argument to document.createElement{,NS} as
Web Components has defined this as a way for custom elements to extend
existing elements.

http://w3c.github.io/webcomponents/spec/custom/#extensions-to-document-interface-to-instantiate
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78799110
Add support for export statements with a "from" clause.

This is part of #406
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78799433
Use "<" instead of ".<" in compiler messages.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78802639
Remove redundant method JSTypeExpression.getRootNode and all references to it.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78803327
Extend ExpressionDecomposer to handle more expression types
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78850246
Merge pull request #681 from Tom9729/ant-sourcemap-fix

 #588 Fix for CompileTask source maps

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78855413
Add HTMLMediaElement.oncanplaythrough to the externs.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78864650