1. Added new flag verify_gc_contains and moved all the asserts that do a

runtime/vm/heap.h

 // 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.
 
 #ifndef RUNTIME_VM_HEAP_H_
 #define RUNTIME_VM_HEAP_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/flags.h"
@@ skipping 70 matching lines @@
   void AllocateExternal(intptr_t size, Space space);
   void FreeExternal(intptr_t size, Space space);
   // Move external size from new to old space. Does not by itself trigger GC.
   void PromoteExternal(intptr_t size);
 
   // Heap contains the specified address.
   bool Contains(uword addr) const;
   bool NewContains(uword addr) const;
   bool OldContains(uword addr) const;
   bool CodeContains(uword addr) const;
+  bool DataContains(uword addr) const;
 
   void IterateObjects(ObjectVisitor* visitor) const;
   void IterateOldObjects(ObjectVisitor* visitor) const;
   void IterateOldObjectsNoEmbedderPages(ObjectVisitor* visitor) const;
   void IterateObjectPointers(ObjectVisitor* visitor) const;
 
   // Find an object by visiting all pointers in the specified heap space,
   // the 'visitor' is used to determine if an object is found or not.
   // The 'visitor' function should be set up to return true if the
   // object is found, traversal through the heap space stops at that
@@ skipping 285 matching lines @@
 // Note: During this scope, the code pages are non-executable.
 class WritableVMIsolateScope : StackResource {
  public:
   explicit WritableVMIsolateScope(Thread* thread);
   ~WritableVMIsolateScope();
 };
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_HEAP_H_