Fix crash with --noopt and no_snapshot: initialize megamorphic cache table before first code is run.

runtime/vm/object.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/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 13338 matching lines @@
 RawMegamorphicCache* MegamorphicCache::New() {
   MegamorphicCache& result = MegamorphicCache::Handle();
   { RawObject* raw = Object::Allocate(MegamorphicCache::kClassId,
                                       MegamorphicCache::InstanceSize(),
                                       Heap::kOld);
     NoSafepointScope no_safepoint;
     result ^= raw;
   }
   const intptr_t capacity = kInitialCapacity;
   const Array& buckets = Array::Handle(Array::New(kEntryLength * capacity));
+  ASSERT(Isolate::Current()->megamorphic_cache_table()->miss_handler() != NULL);
   const Function& handler = Function::Handle(
       Isolate::Current()->megamorphic_cache_table()->miss_handler());
   for (intptr_t i = 0; i < capacity; ++i) {
     SetEntry(buckets, i, smi_illegal_cid(), handler);
   }
   result.set_buckets(buckets);
   result.set_mask(capacity - 1);
   result.set_filled_entry_count(0);
   return result.raw();
 }
@@ skipping 7605 matching lines @@
   return tag_label.ToCString();
 }
 
 
 void UserTag::PrintJSONImpl(JSONStream* stream, bool ref) const {
   Instance::PrintJSONImpl(stream, ref);
 }
 
 
 }  // namespace dart