Improves Long.fromNumber for common cases and avoids unnecessary recursion.
Improves Long.fromNumber for common cases and avoids unnecessary recursion.

Taking shortcuts for special cases adds overhead the remaining 2^64-1 cases. That is nicely explained by Kevin's article here:
http://smallwig.blogspot.com/2010/03/little-optimization-that-couldnt.html

RELNOTES: improve Long.fromNumber performance.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=209217141

google/closure-library,google/closure-library,google/closure-library,lucidsoftware/closure-library,teppeis/closure-library,teppeis/closure-library,teppeis/closure-library,google/closure-library,lucidsoftware/closure-library,google/closure-library,lucidsoftware/closure-library,teppeis/closure-library,lucidsoftware/closure-library