Rename usages of goog.date.fromIsoString() to goog.date.DateTime.fromIsoString().
Rename usages of goog.date.fromIsoString() to goog.date.DateTime.fromIsoString().

This change is being made so goog.date.fromIsoString() (now deprecated) can be removed in favor of goog.date.DateTime.fromIsoString().

More information: go/fromIsoString-rename-lsc

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=179700072

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