Revert of Always give class literals a block scope

src/compiler/ast-graph-builder.cc

 // Copyright 2014 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/compiler/ast-graph-builder.h"
 
 #include "src/compiler.h"
 #include "src/compiler/ast-loop-assignment-analyzer.h"
 #include "src/compiler/control-builders.h"
 #include "src/compiler/js-type-feedback.h"
@@ skipping 1509 matching lines @@
 
   // Create node to instantiate a new closure.
   PretenureFlag pretenure = expr->pretenure() ? TENURED : NOT_TENURED;
   const Operator* op = javascript()->CreateClosure(shared_info, pretenure);
   Node* value = NewNode(op);
   ast_context()->ProduceValue(value);
 }
 
 
 void AstGraphBuilder::VisitClassLiteral(ClassLiteral* expr) {
-  // Visit declarations and class literal in a block scope.
-  if (expr->scope()->ContextLocalCount() > 0) {
-    Node* context = BuildLocalBlockContext(expr->scope());
-    ContextScope scope(this, expr->scope(), context);
-    VisitDeclarations(expr->scope()->declarations());
+  if (expr->scope() == NULL) {
+    // Visit class literal in the same scope, no declarations.
     VisitClassLiteralContents(expr);
   } else {
-    VisitDeclarations(expr->scope()->declarations());
-    VisitClassLiteralContents(expr);
+    // Visit declarations and class literal in a block scope.
+    if (expr->scope()->ContextLocalCount() > 0) {
+      Node* context = BuildLocalBlockContext(expr->scope());
+      ContextScope scope(this, expr->scope(), context);
+      VisitDeclarations(expr->scope()->declarations());
+      VisitClassLiteralContents(expr);
+    } else {
+      VisitDeclarations(expr->scope()->declarations());
+      VisitClassLiteralContents(expr);
+    }
   }
 }
 
 
 void AstGraphBuilder::VisitClassLiteralContents(ClassLiteral* expr) {
   Node* class_name = expr->raw_name() ? jsgraph()->Constant(expr->name())
                                       : jsgraph()->UndefinedConstant();
 
   // The class name is expected on the operand stack.
   environment()->Push(class_name);
@@ skipping 77 matching lines @@
 
   // Set both the prototype and constructor to have fast properties, and also
   // freeze them in strong mode.
   environment()->Pop();  // proto
   environment()->Pop();  // literal
   const Operator* op =
       javascript()->CallRuntime(Runtime::kFinalizeClassDefinition, 2);
   literal = NewNode(op, literal, proto);
 
   // Assign to class variable.
-  if (expr->class_variable_proxy() != nullptr) {
+  if (expr->scope() != NULL) {
+    DCHECK_NOT_NULL(expr->class_variable_proxy());
     Variable* var = expr->class_variable_proxy()->var();
     FrameStateBeforeAndAfter states(this, BailoutId::None());
     VectorSlotPair feedback = CreateVectorSlotPair(
         expr->NeedsProxySlot() ? expr->ProxySlot()
                                : FeedbackVectorSlot::Invalid());
     BuildVariableAssignment(var, literal, Token::INIT_CONST, feedback,
                             BailoutId::None(), states);
   }
   ast_context()->ProduceValue(literal);
 }
@@ skipping 2632 matching lines @@
     // Phi does not exist yet, introduce one.
     value = NewPhi(inputs, value, control);
     value->ReplaceInput(inputs - 1, other);
   }
   return value;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8