Remove the SanitizedHtml subtype from `soydata_aliases.js`
Remove the SanitizedHtml subtype from `soydata_aliases.js`

This class was non-instantiable and just a holder, so the only usecase was for `instanceof` tests and similar reflective `prototype` analysis.

GITHUB_BREAKING_CHANGES=code testing types against `soydata.SanitizedHtml` should instead use `goog.soy.data.SanitizedHtml` or possibly factory methods like `soy.createSanitizedHtml`

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=355684030

google/closure-templates,google/closure-templates,google/closure-templates,google/closure-templates,google/closure-templates