Revert of Use same blob format for internal and external snapshots.

src/snapshot-common.cc

Index: src/snapshot-common.cc
diff --git a/src/snapshot-common.cc b/src/snapshot-common.cc
index 80463542665ff7e2ed23947731fed7684da17d7a..f06f38a19983665b1f233251a3a0692169601688 100644
--- a/src/snapshot-common.cc
+++ b/src/snapshot-common.cc
@@ -14,56 +14,34 @@
 namespace v8 {
 namespace internal {
 
-bool Snapshot::HaveASnapshotToStartFrom() {
-  return SnapshotBlob().data != NULL;
+
+bool Snapshot::Initialize(Isolate* isolate) {
+  if (size_ > 0) {
+    base::ElapsedTimer timer;
+    if (FLAG_profile_deserialization) timer.Start();
+
+    SnapshotData snapshot_data(data_, size_);
+    Deserializer deserializer(&snapshot_data);
+    bool success = isolate->Init(&deserializer);
+    if (FLAG_profile_deserialization) {
+      double ms = timer.Elapsed().InMillisecondsF();
+      PrintF("[Snapshot loading and deserialization took %0.3f ms]\n", ms);
+    }
+    return success;
+  }
+  return false;
 }
 
 
-const Vector<const byte> Snapshot::StartupSnapshot() {
-  DCHECK(HaveASnapshotToStartFrom());
-  const v8::StartupData blob = SnapshotBlob();
-  SnapshotByteSource source(blob.data, blob.raw_size);
-  const byte* data;
-  int length;
-  bool success = source.GetBlob(&data, &length);
-  CHECK(success);
-  return Vector<const byte>(data, length);
-}
-
-
-const Vector<const byte> Snapshot::ContextSnapshot() {
-  DCHECK(HaveASnapshotToStartFrom());
-  const v8::StartupData blob = SnapshotBlob();
-  SnapshotByteSource source(blob.data, blob.raw_size);
-  const byte* data;
-  int length;
-  bool success = source.GetBlob(&data, &length);
-  success &= source.GetBlob(&data, &length);
-  CHECK(success);
-  return Vector<const byte>(data, length);
-}
-
-
-bool Snapshot::Initialize(Isolate* isolate) {
-  if (!HaveASnapshotToStartFrom()) return false;
-  base::ElapsedTimer timer;
-  if (FLAG_profile_deserialization) timer.Start();
-
-  SnapshotData snapshot_data(StartupSnapshot());
-  Deserializer deserializer(&snapshot_data);
-  bool success = isolate->Init(&deserializer);
-  if (FLAG_profile_deserialization) {
-    double ms = timer.Elapsed().InMillisecondsF();
-    PrintF("[Snapshot loading and deserialization took %0.3f ms]\n", ms);
-  }
-  return success;
+bool Snapshot::HaveASnapshotToStartFrom() {
+  return size_ != 0;
 }
 
 
 Handle<Context> Snapshot::NewContextFromSnapshot(Isolate* isolate) {
-  if (!HaveASnapshotToStartFrom()) return Handle<Context>();
+  if (context_size_ == 0) return Handle<Context>();
 
-  SnapshotData snapshot_data(ContextSnapshot());
+  SnapshotData snapshot_data(context_data_, context_size_);
   Deserializer deserializer(&snapshot_data);
   Object* root;
   deserializer.DeserializePartial(isolate, &root);
@@ -71,4 +49,15 @@
   return Handle<Context>(Context::cast(root));
 }
 
+
+#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+// Dummy implementations of Set*FromFile(..) APIs.
+//
+// These are meant for use with snapshot-external.cc. Should this file
+// be compiled with those options we just supply these dummy implementations
+// below. This happens when compiling the mksnapshot utility.
+void SetNativesFromFile(StartupData* data) { CHECK(false); }
+void SetSnapshotFromFile(StartupData* data) { CHECK(false); }
+#endif  // V8_USE_EXTERNAL_STARTUP_DATA
+
 } }  // namespace v8::internal