RELNOTES[INC]: Change goog.soy.TextTemplate to return string.
RELNOTES[INC]: Change goog.soy.TextTemplate to return string.

I'm going to delete goog.soy.TextType so I don't bother changing it.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=250635123

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