Add integration tests to make sure that SanitizedContent directionality is correctly preserved.
Add integration tests to make sure that SanitizedContent directionality is correctly preserved.

This will help ensure that future work to make the bidiSpanWrapp and bidiUnicodeWrap directives streaming retain this behavior.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=172505429

yext/closure-templates,google/closure-templates,Medium/closure-templates,Medium/closure-templates,Medium/closure-templates,Medium/closure-templates,yext/closure-templates,yext/closure-templates,yext/closure-templates,Medium/closure-templates,google/closure-templates,google/closure-templates,google/closure-templates,google/closure-templates