[parser] Delete has_seen_proto in ObjectLiteral.

For an object literal, has_seen_proto is needed to create the
BoilerplateDescription. When iterating over the object
properties in the AST, has_seen_proto can easily be computed. The
flag in the ObjectLiteral is unnecessary.

R=verwaest@chromium.org

BUG=v8:5625

Review-Url: https://codereview.chromium.org/2646333002
Cr-Commit-Position: refs/heads/master@{#42601}

src/ast/ast.cc

@@ -520,7 +520,6 @@ void ObjectLiteral::InitDepthAndFlags() {
   for (int i = 0; i < properties()->length(); i++) {
     ObjectLiteral::Property* property = properties()->at(i);
     if (!IsBoilerplateProperty(property)) {
-      DCHECK(has_seen_proto());
       is_simple = false;
       continue;
     }
@@ -584,9 +583,14 @@ void ObjectLiteral::BuildConstantProperties(Isolate* isolate) {
   if (!constant_properties_.is_null()) return;
 
   int index_keys = 0;
+  bool has_seen_proto = false;
   for (int i = 0; i < properties()->length(); i++) {
     ObjectLiteral::Property* property = properties()->at(i);
-    if (!IsBoilerplateProperty(property) || property->is_computed_name()) {
+    if (!IsBoilerplateProperty(property)) {
+      has_seen_proto = true;
+      continue;
+    }
+    if (property->is_computed_name()) {
       continue;
     }
 
@@ -602,7 +606,7 @@ void ObjectLiteral::BuildConstantProperties(Isolate* isolate) {
   Handle<BoilerplateDescription> constant_properties =
       isolate->factory()->NewBoilerplateDescription(
           boilerplate_properties_, properties()->length() - index_keys,
-          has_seen_proto());
+          has_seen_proto);
 
   int position = 0;
   for (int i = 0; i < properties()->length(); i++) {

src/ast/ast.h

@@ -1402,9 +1402,6 @@ class ObjectLiteral final : public MaterializedLiteral {
   bool has_rest_property() const {
     return HasRestPropertyField::decode(bit_field_);
   }
-  bool has_seen_proto() const {
-    return HasSeenProtoPropertyField::decode(bit_field_);
-  }
 
   // Decide if a property should be in the object boilerplate.
   static bool IsBoilerplateProperty(Property* property);
@@ -1476,7 +1473,7 @@ class ObjectLiteral final : public MaterializedLiteral {
   friend class AstNodeFactory;
 
   ObjectLiteral(ZoneList<Property*>* properties, int literal_index,
-                uint32_t boilerplate_properties, bool has_seen_proto, int pos,
+                uint32_t boilerplate_properties, int pos,
                 bool has_rest_property)
       : MaterializedLiteral(literal_index, pos, kObjectLiteral),
         boilerplate_properties_(boilerplate_properties),
@@ -1484,8 +1481,7 @@ class ObjectLiteral final : public MaterializedLiteral {
     bit_field_ |= FastElementsField::encode(false) |
                   HasElementsField::encode(false) |
                   MayStoreDoublesField::encode(false) |
-                  HasRestPropertyField::encode(has_rest_property) |
-                  HasSeenProtoPropertyField::encode(has_seen_proto);
+                  HasRestPropertyField::encode(has_rest_property);
   }
 
   static int parent_num_ids() { return MaterializedLiteral::num_ids(); }
@@ -1503,8 +1499,6 @@ class ObjectLiteral final : public MaterializedLiteral {
       : public BitField<bool, HasElementsField::kNext, 1> {};
   class HasRestPropertyField
       : public BitField<bool, MayStoreDoublesField::kNext, 1> {};
-  class HasSeenProtoPropertyField
-      : public BitField<bool, HasRestPropertyField::kNext, 1> {};
 };
 
 
@@ -3351,11 +3345,10 @@ class AstNodeFactory final BASE_EMBEDDED {
 
   ObjectLiteral* NewObjectLiteral(
       ZoneList<ObjectLiteral::Property*>* properties, int literal_index,
-      uint32_t boilerplate_properties, bool has_seen_proto, int pos,
-      bool has_rest_property) {
+      uint32_t boilerplate_properties, int pos, bool has_rest_property) {
     return new (zone_)
-        ObjectLiteral(properties, literal_index, boilerplate_properties,
-                      has_seen_proto, pos, has_rest_property);
+        ObjectLiteral(properties, literal_index, boilerplate_properties, pos,
+                      has_rest_property);
   }
 
   ObjectLiteral::Property* NewObjectLiteralProperty(

src/parsing/parser-base.h

@@ -2552,7 +2552,6 @@ typename ParserBase<Impl>::ExpressionT ParserBase<Impl>::ParseObjectLiteral(
   typename Types::ObjectPropertyList properties =
       impl()->NewObjectPropertyList(4);
   int number_of_boilerplate_properties = 0;
-  bool has_seen_proto = false;
 
   bool has_computed_names = false;
   bool has_rest_property = false;
@@ -2576,9 +2575,7 @@ typename ParserBase<Impl>::ExpressionT ParserBase<Impl>::ParseObjectLiteral(
       has_rest_property = true;
     }
 
-    if (!impl()->IsBoilerplateProperty(property)) {
-      has_seen_proto = true;
-    } else if (!has_computed_names) {
+    if (impl()->IsBoilerplateProperty(property) && !has_computed_names) {
       // Count CONSTANT or COMPUTED properties to maintain the enumeration
       // order.
       number_of_boilerplate_properties++;
@@ -2599,8 +2596,8 @@ typename ParserBase<Impl>::ExpressionT ParserBase<Impl>::ParseObjectLiteral(
   int literal_index = function_state_->NextMaterializedLiteralIndex();
 
   return factory()->NewObjectLiteral(properties, literal_index,
-                                     number_of_boilerplate_properties,
-                                     has_seen_proto, pos, has_rest_property);
+                                     number_of_boilerplate_properties, pos,
+                                     has_rest_property);
 }
 
 template <typename Impl>

src/parsing/preparser.h

@@ -595,8 +595,7 @@ class PreParserFactory {
   }
   PreParserExpression NewObjectLiteral(PreParserExpressionList properties,
                                        int literal_index,
-                                       int boilerplate_properties,
-                                       bool has_seen_proto, int pos,
+                                       int boilerplate_properties, int pos,
                                        bool has_rest_property) {
     return PreParserExpression::ObjectLiteral(properties.variables_);
   }