Tighten CheckRegExp so fewer false positives are generated.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=49111760
Update angular.js externs to show angular.bootstrap returns an angular.$injector.

Also update get and invoke to return {?} instead of {*}, since the ALL type is type-checked. In other words, this would cause a problem:

var injector = angular.bootstrap(blah);
injector.get('myFactory').newInstance();

Since the ALL type may represent a non-function type, so it can't be gauranteed to be a callable expression. On the other hand, {?} is never type checked, and allows callers to cast the return value.

Maybe if AngularJS team does closer integration with Closure compiler in the future they can map these to concrete types :)
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=49116170