[snapshot] remove metadata field.

src/snapshot/snapshot.h

 // Copyright 2006-2008 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.
 
 #ifndef V8_SNAPSHOT_SNAPSHOT_H_
 #define V8_SNAPSHOT_SNAPSHOT_H_
 
 #include "src/snapshot/partial-serializer.h"
 #include "src/snapshot/startup-serializer.h"
 
 namespace v8 {
 namespace internal {
 
 // Forward declarations.
 class Isolate;
 class PartialSerializer;
 class StartupSerializer;
 
 class Snapshot : public AllStatic {
  public:
-  class Metadata {
-   public:
-    explicit Metadata(uint32_t data = 0) : data_(data) {}
-    bool embeds_script() { return EmbedsScriptBits::decode(data_); }
-    void set_embeds_script(bool v) {
-      data_ = EmbedsScriptBits::update(data_, v);
-    }
-
-    uint32_t& RawValue() { return data_; }
-
-   private:
-    class EmbedsScriptBits : public BitField<bool, 0, 1> {};
-    uint32_t data_;
-  };
-
   // Initialize the Isolate from the internal snapshot. Returns false if no
   // snapshot could be found.
   static bool Initialize(Isolate* isolate);
   // Create a new context using the internal partial snapshot.
   static MaybeHandle<Context> NewContextFromSnapshot(
       Isolate* isolate, Handle<JSGlobalProxy> global_proxy);
 
   static bool HaveASnapshotToStartFrom(Isolate* isolate);
 
   static bool EmbedsScript(Isolate* isolate);
 
   static uint32_t SizeOfFirstPage(Isolate* isolate, AllocationSpace space);
 
 
   // To be implemented by the snapshot source.
   static const v8::StartupData* DefaultSnapshotBlob();
 
   static v8::StartupData CreateSnapshotBlob(
       const StartupSerializer& startup_ser,
-      const PartialSerializer& context_ser, Snapshot::Metadata metadata);
+      const PartialSerializer& context_ser);
 
 #ifdef DEBUG
   static bool SnapshotIsValid(v8::StartupData* snapshot_blob);
 #endif  // DEBUG
 
  private:
   static Vector<const byte> ExtractStartupData(const v8::StartupData* data);
   static Vector<const byte> ExtractContextData(const v8::StartupData* data);
-  static Metadata ExtractMetadata(const v8::StartupData* data);
 
   // Snapshot blob layout:
-  // [0] metadata
-  // [1 - 6] pre-calculated first page sizes for paged spaces
-  // [7] serialized start up data length
+  // [0 - 5] pre-calculated first page sizes for paged spaces
+  // [6] serialized start up data length
   // ... serialized start up data
   // ... serialized context data
 
   static const int kNumPagedSpaces = LAST_PAGED_SPACE - FIRST_PAGED_SPACE + 1;
 
-  static const int kMetadataOffset = 0;
-  static const int kFirstPageSizesOffset = kMetadataOffset + kInt32Size;
+  static const int kFirstPageSizesOffset = 0;
   static const int kStartupLengthOffset =
       kFirstPageSizesOffset + kNumPagedSpaces * kInt32Size;
   static const int kStartupDataOffset = kStartupLengthOffset + kInt32Size;
 
   static int ContextOffset(int startup_length) {
     return kStartupDataOffset + startup_length;
   }
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(Snapshot);
 };
@@ skipping 34 matching lines @@
   static const int kCheckSumOffset = kMagicNumberOffset + kInt32Size;
   static const int kNumReservationsOffset = kCheckSumOffset + kInt32Size;
   static const int kPayloadLengthOffset = kNumReservationsOffset + kInt32Size;
   static const int kHeaderSize = kPayloadLengthOffset + kInt32Size;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_SNAPSHOT_SNAPSHOT_H_