docs: function trustAs(type, trustedValue) {
        var Constructor = (byType.hasOwnProperty(type) ? byType[type] : null);
        if (!Constructor) {
          throw $sceMinErr('icontext',
              'Attempted to trust a value in invalid context. Context: {0}; Value: {1}',
              type, trustedValue);
        }
        if (trustedValue === null || isUndefined(trustedValue) || trustedValue === '') {
          return trustedValue;
        }
        // All the current contexts in SCE_CONTEXTS happen to be strings.  In order to avoid trusting
        // mutable objects, we ensure here that the value passed in is actually a string.
        if (typeof trustedValue !== 'string') {
          throw $sceMinErr('itype',
              'Attempted to trust a non-string value in a content requiring a string: Context: {0}',
              type);
        }
        return new Constructor(trustedValue);
      }