Refactor requeststats in webchannel to not execute code on goog.require
Refactor requeststats in webchannel to not execute code on goog.require

This allows the closure compiler to prune ~8kb from a js binary if it determines that the webchannel exports are never called/referenced.

RELNOTES: Bugfix that allows compiler to optimize out closure deps

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=246425113

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