function SanitizedContentSubclass(content, kind) {
  // IMPORTANT! No superclass chaining to avoid exception being thrown.
  this.content = content;
  this.contentKind = kind;
}
Instantiable subclass of SanitizedContent.

This is a spoof for sanitized content that isn't robust enough to get
through Soy's escaping functions but is good enough for the checks here.

@constructor
@param {string} content The text.
@param {goog.soy.data.SanitizedContentKind} kind The kind of safe content.
@extends {goog.soy.data.SanitizedContent}