deps: backport f795a79 from upstream V8

deps/v8/src/parsing/parser.h

@@ -880,6 +880,8 @@ class Parser : public ParserBase<ParserTraits> {
     PatternContext SetAssignmentContextIfNeeded(Expression* node);
     PatternContext SetInitializerContextIfNeeded(Expression* node);
 
+    void RewriteParameterScopes(Expression* expr);
+
     Variable* CreateTempVar(Expression* value = nullptr);
 
     AstNodeFactory* factory() const { return parser_->factory(); }

deps/v8/src/parsing/pattern-rewriter.cc

@@ -387,6 +387,37 @@ void Parser::PatternRewriter::VisitRewritableExpression(
   return set_context(old_context);
 }
 
+// Two cases for scope rewriting the scope of default parameters:
+// - Eagerly parsed arrow functions are initially parsed as having
+//   expressions in the enclosing scope, but when the arrow is encountered,
+//   need to be in the scope of the function.
+// - When an extra declaration scope needs to be inserted to account for
+//   a sloppy eval in a default parameter or function body, the expressions
+//   needs to be in that new inner scope which was added after initial
+//   parsing.
+// Each of these cases can be handled by rewriting the contents of the
+// expression to the current scope. The source scope is typically the outer
+// scope when one case occurs; when both cases occur, both scopes need to
+// be included as the outer scope. (Both rewritings still need to be done
+// to account for lazily parsed arrow functions which hit the second case.)
+// TODO(littledan): Remove the outer_scope parameter of
+//                  RewriteParameterInitializerScope
+void Parser::PatternRewriter::RewriteParameterScopes(Expression* expr) {
+  if (!IsBindingContext()) return;
+  if (descriptor_->declaration_kind != DeclarationDescriptor::PARAMETER) return;
+  if (!scope()->is_arrow_scope() && !scope()->is_block_scope()) return;
+
+  // Either this scope is an arrow scope or a declaration block scope.
+  DCHECK(scope()->is_declaration_scope());
+
+  if (scope()->outer_scope()->is_arrow_scope() && scope()->is_block_scope()) {
+    RewriteParameterInitializerScope(parser_->stack_limit(), expr,
+                                     scope()->outer_scope()->outer_scope(),
+                                     scope());
+  }
+  RewriteParameterInitializerScope(parser_->stack_limit(), expr,
+                                   scope()->outer_scope(), scope());
+}
 
 void Parser::PatternRewriter::VisitObjectLiteral(ObjectLiteral* pattern,
                                                  Variable** temp_var) {
@@ -396,6 +427,11 @@ void Parser::PatternRewriter::VisitObjectLiteral(ObjectLiteral* pattern,
 
   for (ObjectLiteralProperty* property : *pattern->properties()) {
     PatternContext context = SetInitializerContextIfNeeded(property->value());
+
+    // Computed property names contain expressions which might require
+    // scope rewriting.
+    if (!property->key()->IsLiteral()) RewriteParameterScopes(property->key());
+
     RecurseIntoSubpattern(
         property->value(),
         factory()->NewProperty(factory()->NewVariableProxy(temp),
@@ -668,32 +704,8 @@ void Parser::PatternRewriter::VisitAssignment(Assignment* node) {
                                       RelocInfo::kNoPosition);
   }
 
-  // Two cases for scope rewriting the scope of default parameters:
-  // - Eagerly parsed arrow functions are initially parsed as having
-  //   initializers in the enclosing scope, but when the arrow is encountered,
-  //   need to be in the scope of the function.
-  // - When an extra declaration scope needs to be inserted to account for
-  //   a sloppy eval in a default parameter or function body, the initializer
-  //   needs to be in that new inner scope which was added after initial
-  //   parsing.
-  // Each of these cases can be handled by rewriting the contents of the
-  // initializer to the current scope. The source scope is typically the outer
-  // scope when one case occurs; when both cases occur, both scopes need to
-  // be included as the outer scope. (Both rewritings still need to be done
-  // to account for lazily parsed arrow functions which hit the second case.)
-  // TODO(littledan): Remove the outer_scope parameter of
-  //                  RewriteParameterInitializerScope
-  if (IsBindingContext() &&
-      descriptor_->declaration_kind == DeclarationDescriptor::PARAMETER &&
-      (scope()->is_arrow_scope() || scope()->is_block_scope())) {
-    if (scope()->outer_scope()->is_arrow_scope() && scope()->is_block_scope()) {
-      RewriteParameterInitializerScope(parser_->stack_limit(), initializer,
-                                       scope()->outer_scope()->outer_scope(),
-                                       scope());
-    }
-    RewriteParameterInitializerScope(parser_->stack_limit(), initializer,
-                                     scope()->outer_scope(), scope());
-  }
+  // Initializer may have been parsed in the wrong scope.
+  RewriteParameterScopes(initializer);
 
   PatternContext old_context = SetAssignmentContextIfNeeded(initializer);
   RecurseIntoSubpattern(node->target(), value);

deps/v8/test/mjsunit/regress/regress-crbug-620119.js

@@ -0,0 +1,8 @@
+// Copyright 2016 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.
+
+// Flags: --no-lazy
+
+assertEquals(0, ((x, {[(x = function() { y = 0 }, "foo")]: y = eval(1)}) => { x(); return y })(42, {}));
+assertEquals(0, (function (x, {[(x = function() { y = 0 }, "foo")]: y = eval(1)}) { x(); return y })(42, {}));