Extend the jasmine externs.

add partial definition of jasmine.Spec
add 'calls' to jasmine.Spy
add/fix return types to jasmine.Spy methods
add 'this' type to 'it' handlers to allow 'this.fail'
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=53705652
Fix the function signature for WebGLContextEvent
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=53706870
Fix annotation of chrome permissions apis: Permissions is not an actual
type, but a pseudo-type describing an array with a particular set of
values.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=53734179
This change had to be rolled-back, since it breaks some users of the Java API.
See the updated comment and new test case for reasoning.

The error level shouldn't effect compiler output. Fixes issue 1079

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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=53756243