Eagerly declare variables in ParseVariableDeclarations where possible

src/parsing/parser.h

Index: src/parsing/parser.h
diff --git a/src/parsing/parser.h b/src/parsing/parser.h
index 87b6a910a458bb231687a0a4fb268d0194f99865..638b4ff761123bddd42b60aa6cedd500a04cc337 100644
--- a/src/parsing/parser.h
+++ b/src/parsing/parser.h
@@ -878,10 +878,10 @@ class Parser : public ParserBase<ParserTraits> {
     bool* ok_;
   };
 
-
-  void ParseVariableDeclarations(VariableDeclarationContext var_context,
-                                 DeclarationParsingResult* parsing_result,
-                                 bool* ok);
+  Block* ParseVariableDeclarations(VariableDeclarationContext var_context,
+                                   DeclarationParsingResult* parsing_result,
+                                   ZoneList<const AstRawString*>* names,
+                                   bool* ok);
   Statement* ParseExpressionOrLabelledStatement(
       ZoneList<const AstRawString*>* labels, bool* ok);
   IfStatement* ParseIfStatement(ZoneList<const AstRawString*>* labels,