Editorial: add _direction_ to BackreferenceMatcher's param list

... to resolve BackreferenceMatcher's reference to _direction_ at step 1.f

spec.html

@@ -30425,7 +30425,7 @@ <h1>AtomEscape</h1>
         <emu-alg>
           1. Evaluate |DecimalEscape| to obtain an integer _n_.
           1. Assert: _n_ &le; _NcapturingParens_.
-          1. Call BackreferenceMatcher(_n_) and return its Matcher result.
+          1. Call BackreferenceMatcher(_n_, _direction_) and return its Matcher result.
         </emu-alg>
         <p>The production <emu-grammar>AtomEscape :: CharacterEscape</emu-grammar> evaluates as follows:</p>
         <emu-alg>
@@ -30446,12 +30446,12 @@ <h1>AtomEscape</h1>
           1. Search the enclosing |Pattern| for an instance of a |GroupSpecifier| for a |RegExpIdentifierName| which has a StringValue equal to the StringValue of the |RegExpIdentifierName| contained in |GroupName|.
           1. Assert: A unique such |GroupSpecifier| is found.
           1. Let _parenIndex_ be the number of left-capturing parentheses in the entire regular expression that occur to the left of the located |GroupSpecifier|. This is the total number of <emu-grammar>Atom :: `(` GroupSpecifier Disjunction `)`</emu-grammar> Parse Nodes prior to or enclosing the located |GroupSpecifier|.
-          1. Call BackreferenceMatcher(_parenIndex_) and return its Matcher result.
+          1. Call BackreferenceMatcher(_parenIndex_, _direction_) and return its Matcher result.
         </emu-alg>
 
         <emu-clause id="sec-backreference-matcher" aoid="BackreferenceMatcher">
-          <h1>Runtime Semantics: BackreferenceMatcher ( _n_ )</h1>
-          <p>The abstract operation BackreferenceMatcher takes one argument, an integer _n_, and performs the following steps:</p>
+          <h1>Runtime Semantics: BackreferenceMatcher ( _n_, _direction_ )</h1>
+          <p>The abstract operation BackreferenceMatcher takes two arguments, an integer _n_ and an integer _direction_, and performs the following steps:</p>
           <emu-alg>
             1. Return an internal Matcher closure that takes two arguments, a State _x_ and a Continuation _c_, and performs the following steps:
               1. Let _cap_ be _x_'s _captures_ List.