[Bindings] Create and use V8 context snapshots

gin/public/isolate_holder.h

Index: gin/public/isolate_holder.h
diff --git a/gin/public/isolate_holder.h b/gin/public/isolate_holder.h
index e28462138657217b9b00f785c22e55e4c5502d9d..fb7ffe0880f0e3f5a14fb445a2d0b0f516b3ab18 100644
--- a/gin/public/isolate_holder.h
+++ b/gin/public/isolate_holder.h
@@ -59,7 +59,9 @@ class GIN_EXPORT IsolateHolder {
                 AccessMode access_mode);
   IsolateHolder(scoped_refptr<base::SingleThreadTaskRunner> task_runner,
                 AccessMode access_mode,
-                AllowAtomicsWaitMode atomics_wait_mode);
+                AllowAtomicsWaitMode atomics_wait_mode,
+                intptr_t* reference_table,
+                v8::StartupData* startup_data);
 
   // This constructor is to create V8 snapshot for Blink.
   // Note this constructor calls isolate->Enter() internally.
@@ -110,11 +112,13 @@ class GIN_EXPORT IsolateHolder {
   }
 
  private:
+  void SetUp(scoped_refptr<base::SingleThreadTaskRunner> task_runner);
+
+  std::unique_ptr<v8::SnapshotCreator> snapshot_creator_;
   v8::Isolate* isolate_;
   std::unique_ptr<PerIsolateData> isolate_data_;
   std::unique_ptr<RunMicrotasksObserver> task_observer_;
   std::unique_ptr<V8IsolateMemoryDumpProvider> isolate_memory_dump_provider_;
-  std::unique_ptr<v8::SnapshotCreator> snapshot_creator_;
   AccessMode access_mode_;
 
   DISALLOW_COPY_AND_ASSIGN(IsolateHolder);