Optimizes goog.math.Long.toString by a having faster code path for numbers that fit in 53 bits.
Optimizes goog.math.Long.toString by a having faster code path for numbers that fit in 53 bits.

RELNOTES: Adds a faster code path for goog.math.Long.toString for numbers fit 53 bits.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=201719079

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