Don't write Code::code_source_map_ in snapshots.

runtime/vm/raw_object_snapshot.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/native_entry.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/snapshot.h"
 #include "vm/stub_code.h"
 #include "vm/symbols.h"
@@ skipping 1425 matching lines @@
                           &result.raw_ptr()->exception_handlers_),
                       reader->PassiveObjectHandle()->raw());
 
   (*reader->PassiveObjectHandle()) ^= reader->ReadObjectImpl(kAsReference);
   result.StorePointer(reinterpret_cast<RawObject*const*>(
                           &result.raw_ptr()->pc_descriptors_),
                       reader->PassiveObjectHandle()->raw());
 
   (*reader->PassiveObjectHandle()) ^= reader->ReadObjectImpl(kAsReference);
   result.StorePointer(reinterpret_cast<RawObject*const*>(
-                          &result.raw_ptr()->code_source_map_),
-                      reader->PassiveObjectHandle()->raw());
-
-  (*reader->PassiveObjectHandle()) ^= reader->ReadObjectImpl(kAsReference);
-  result.StorePointer(reinterpret_cast<RawObject*const*>(
                           &result.raw_ptr()->stackmaps_),
                       reader->PassiveObjectHandle()->raw());
 
   result.StorePointer(&result.raw_ptr()->deopt_info_array_,
                       Array::null());
   result.StorePointer(&result.raw_ptr()->static_calls_target_table_,
                       Array::null());
   result.StorePointer(&result.raw_ptr()->var_descriptors_,
                       LocalVarDescriptors::null());
   result.StorePointer(&result.raw_ptr()->inlined_metadata_,
                       Array::null());
+  result.StorePointer(&result.raw_ptr()->code_source_map_,
+                      CodeSourceMap::null());
   result.StorePointer(&result.raw_ptr()->comments_,
                       Array::null());
   result.StorePointer(&result.raw_ptr()->return_address_metadata_,
                       Object::null());
 
   return result.raw();
 }
 
 
 void RawCode::WriteTo(SnapshotWriter* writer,
@@ skipping 41 matching lines @@
   intptr_t instructions_size = Utils::RoundUp(instr->size_,
                                               OS::PreferredCodeAlignment());
   uword check = Checksum(entry, instructions_size);
   writer->Write<uword>(check);
 #endif
 
   writer->WriteObjectImpl(ptr()->object_pool_, kAsReference);
   writer->WriteObjectImpl(ptr()->owner_, kAsReference);
   writer->WriteObjectImpl(ptr()->exception_handlers_, kAsReference);
   writer->WriteObjectImpl(ptr()->pc_descriptors_, kAsReference);
-  writer->WriteObjectImpl(ptr()->code_source_map_, kAsReference);
   writer->WriteObjectImpl(ptr()->stackmaps_, kAsReference);
 }
 
 
 RawInstructions* Instructions::ReadFrom(SnapshotReader* reader,
                                         intptr_t object_id,
                                         intptr_t tags,
                                         Snapshot::Kind kind,
                                         bool as_reference) {
   UNREACHABLE();
@@ skipping 2250 matching lines @@
     // We do not allow objects with native fields in an isolate message.
     writer->SetWriteException(Exceptions::kArgument,
                               "Illegal argument in isolate message"
                               " : (object is a UserTag)");
   } else {
     UNREACHABLE();
   }
 }
 
 }  // namespace dart