AnalyticalGraphicsInc/cesium — pull request #1006 by shunter (2013-08-02 17:41:33+00:00)
Title: The WeakMap shim should use the built-in version if available.

Firefox and IE11 have built-in support, so we can skip all this workaround junk. Also comment out some parts of the shim that we don't actually need (NodeJS & global versions, and a createStorage helper function).