Remove StringContext handling from DOMString conversion algorithm

Author: lukewarlow

index.bs

@@ -7583,13 +7583,6 @@ value when its bit pattern is interpreted as an unsigned 64-bit integer.
     A JavaScript value |V| is [=converted to an IDL value|converted=]
     to an IDL {{DOMString}} value by running the following algorithm:
 
-    1.  If the conversion is to an IDL type [=extended attribute associated with|associated with=] the
-        [{{StringContext}}] extended attribute, then set |V| to the result of [=validate the string in context=], passing
-        [=this=], |V|, the {{StringContext}} extended attribute [=identifier=], and the [=identifier=]
-        of the [{{StringContext}}] extended attribute [=related construct=].
-
-        Note: That algorithm may [=JavaScript/throw=] a <l spec=ecmascript>{{TypeError}}</l>.
-
     1.  If |V| is <emu-val>null</emu-val> and the conversion is to an IDL type
         [=extended attribute associated with|associated with=] the [{{LegacyNullToEmptyString}}] extended
         attribute, then return the {{DOMString}} value that represents the empty string.