[cleanup] Remove dead code from Variable and simplify PatternRewriter slightly

src/parsing/pattern-rewriter.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/ast/ast.h"
 #include "src/messages.h"
 #include "src/parsing/parameter-initializer-rewriter.h"
 #include "src/parsing/parser.h"
 
 namespace v8 {
@@ skipping 49 matching lines @@
 Expression* Parser::PatternRewriter::RewriteDestructuringAssignment(
     Parser* parser, Assignment* assignment, Scope* scope) {
   DCHECK_NOT_NULL(assignment);
   DCHECK_EQ(Token::ASSIGN, assignment->op());
   auto to_rewrite = parser->factory()->NewRewritableExpression(assignment);
   RewriteDestructuringAssignment(parser, to_rewrite, scope);
   return to_rewrite->expression();
 }
 
 
-bool Parser::PatternRewriter::IsAssignmentContext(PatternContext c) const {
-  return c == ASSIGNMENT || c == ASSIGNMENT_INITIALIZER;
-}
-
-
-bool Parser::PatternRewriter::IsBindingContext(PatternContext c) const {
-  return c == BINDING || c == INITIALIZER;
-}
-
-
 Parser::PatternRewriter::PatternContext
 Parser::PatternRewriter::SetAssignmentContextIfNeeded(Expression* node) {
   PatternContext old_context = context();
   // AssignmentExpressions may occur in the Initializer position of a
   // SingleNameBinding. Such expressions should not prompt a change in the
   // pattern's context.
   if (node->IsAssignment() && node->AsAssignment()->op() == Token::ASSIGN &&
       !IsInitializerContext()) {
     set_context(ASSIGNMENT);
   }
@@ skipping 608 matching lines @@
 NOT_A_PATTERN(TryFinallyStatement)
 NOT_A_PATTERN(UnaryOperation)
 NOT_A_PATTERN(VariableDeclaration)
 NOT_A_PATTERN(WhileStatement)
 NOT_A_PATTERN(WithStatement)
 NOT_A_PATTERN(Yield)
 
 #undef NOT_A_PATTERN
 }  // namespace internal
 }  // namespace v8