Migrate NoSafepointScope; add constrained concurrent allocation to unit test

runtime/vm/object.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 VM_OBJECT_H_
 #define VM_OBJECT_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 666 matching lines @@
   // Provides non-const access to non-pointer fields within the object. Such
   // access does not need a write barrier, but it is *not* GC-safe, since the
   // object might move, hence must be fully contained within a NoSafepointScope.
   template<typename FieldType>
   FieldType* UnsafeMutableNonPointer(const FieldType* addr) const {
     // Allow pointers at the end of variable-length data, and disallow pointers
     // within the header word.
     ASSERT(Contains(reinterpret_cast<uword>(addr) - 1) &&
            Contains(reinterpret_cast<uword>(addr) - kWordSize));
     // At least check that there is a NoSafepointScope and hope it's big enough.
-    ASSERT(Isolate::Current()->no_safepoint_scope_depth() > 0);
+    ASSERT(Thread::Current()->no_safepoint_scope_depth() > 0);
     return const_cast<FieldType*>(addr);
   }
 
   // Fail at link time if StoreNonPointer or UnsafeMutableNonPointer is
   // instantiated with an object pointer type.
 #define STORE_NON_POINTER_ILLEGAL_TYPE(type)                                   \
   template<typename ValueType>                                                 \
   void StoreNonPointer(Raw##type* const* addr, ValueType value) const {        \
     UnimplementedMethod();                                                     \
   }                                                                            \
@@ skipping 7308 matching lines @@
 
 
 RawObject* MegamorphicCache::GetTargetFunction(const Array& array,
                                                intptr_t index) {
   return array.At((index * kEntryLength) + kTargetFunctionIndex);
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_