Community contributed externs update to HTMLInputElement.

Spec:
* http://www.w3.org/TR/2011/WD-html5-20110405/common-input-element-attributes.html#dom-input-valueasdate
* http://www.w3.org/TR/2011/WD-html5-20110405/common-input-element-attributes.html#dom-input-valueasnumber
* http://www.w3.org/TR/2011/WD-html5-20110405/common-input-element-attributes.html#dom-input-stepup

Fixes issue 1060
Fixes issue 1061
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=50726216
Fix inlining bug in https://code.google.com/p/closure-compiler/issues/detail?id=1053
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=50726739
Automated g4 rollback of changelist 50726739.

*** Reason for rollback ***

Wants to move back to early iteration of the CL.

*** Original change description ***

Fix inlining bug in https://code.google.com/p/closure-compiler/issues/detail?id=1053
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=50728194