Revert of [Interpreter] Remove separate Ignition snapshot.

src/isolate.cc

 // Copyright 2012 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.
 
 #include "src/isolate.h"
 
 #include <stdlib.h>
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
@@ skipping 2238 matching lines @@
 
   // Initialize runtime profiler before deserialization, because collections may
   // occur, clearing/updating ICs.
   runtime_profiler_ = new RuntimeProfiler(this);
 
   // If we are deserializing, read the state into the now-empty heap.
   if (!create_heap_objects) {
     des->Deserialize(this);
   }
   stub_cache_->Initialize();
-  interpreter_->Initialize();
+
+  if (FLAG_ignition) {
+    interpreter_->Initialize();
+  }
 
   // Finish initialization of ThreadLocal after deserialization is done.
   clear_pending_exception();
   clear_pending_message();
   clear_scheduled_exception();
 
   // Deserializing may put strange things in the root array's copy of the
   // stack guard.
   heap_.SetStackLimits();
 
@@ skipping 702 matching lines @@
   // Then check whether this scope intercepts.
   if ((flag & intercept_mask_)) {
     intercepted_flags_ |= flag;
     return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8