Added a typedef for the jQuery AJAX setting object

The jQuery AJAX setting dictionary is a defined dictionary with known fields. When the various methods accept such a dictionary, they expect very specific properties (the developer can indeed add more properties, of course). Adding a typedef for this type of dictionary reduces the need to quote properties.
Currently, $.ajax({url: "/", beforeSend: function (){} ,cache: true,username: "d",xhrFields: {}}) compiles to $.ajax({url:"/",a:function(){},b:!0,c:"d",d:{}}), causing errors.

With the use of the typedef in the various functions, $.ajax({url: "/", type: "post"}) and friends will be minified without renaming the relevant properties, causing the code not to fail anymore.
jQuery externs - fixed a typo

jsonCallback should be jsonpCallback.
jQuery externs - loosened the AJAX setting types

Added Object.<string, *> to the various methods in addition to jQueryAjaxSettings.
Remove duplicate definition of Window.prototype.postMessage
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76359425
Indicate that the Object function returns an Object even if not called as a constructor.

Fixes #589.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76363026
Remove duplicate definition of Window.prototype.document
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76364757
refactor: Move newQualifiedNameNode and newName methods back to NodeUtil but rename them and make them take an AbstractCompiler instead of a CodingConvention so that calls are still not too verbose.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76367877
Improve logging by making Property toString useful
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76369530
Turn down SymbolTable reporting
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76371063
Improve "@const" handling for invariant expressions (simple numeric/boolean/string operations and "new" expressions)
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76372405
Treat @export as a visibility annotation, equivalent to @public. This allows specifying type and description after an @export tag.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76373288
Merge pull request #627 from headcr4sh/localeCompare

Update externs for String.prototype.localeCompare

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76387346
Allow an interface to extend two different interfaces if they don't have any conflicting properties.

Fixes #618
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76390463
Add chrome.copresence API to common chrome_extensions externs.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76435801
Strip goog.module.declareLegacyNamespace so it works in optimized mode.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76447028
Remove duplicate definition of Window.prototype.screen
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76447740
Move some example RefasterJS templates to the opensource directory and include
them in the opensource compiler release.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76468369
Remove unchecked compile warnings
Allow Foo<T> syntax in JSDoc

Fixes #640
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76594228
Merge pull request #644 from pauldraper/pauldraper-build-warnings-1

Remove unchecked compile warnings