Mark goog.global as @const, since it shouldn't generally be modified.
Mark goog.global as @const, since it shouldn't generally be modified.

RELNOTES: n/a

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185037656

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