Changed StackZone and ApiZone to be containers for Zone.

runtime/vm/assembler.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/assembler.h"
 
 #include "platform/utils.h"
 #include "vm/cpu.h"
 #include "vm/heap.h"
 #include "vm/memory_region.h"
 #include "vm/os.h"
 #include "vm/zone.h"
 
 namespace dart {
 
 static uword NewContents(intptr_t capacity) {
-  StackZone* zone = Isolate::Current()->current_zone();
+  Zone* zone = Isolate::Current()->current_zone();
   uword result = zone->AllocUnsafe(capacity);
 #if defined(DEBUG)
   // Initialize the buffer with kBreakPointInstruction to force a break
   // point if we ever execute an uninitialized part of the code buffer.
   Assembler::InitializeMemoryWithBreakpoints(result, capacity);
 #endif
   return result;
 }
 
 
@@ skipping 151 matching lines @@
 
 void Assembler::Unreachable(const char* message) {
   const char* format = "Unreachable: %s";
   const intptr_t len = OS::SNPrint(NULL, 0, format, message);
   char* buffer = reinterpret_cast<char*>(malloc(len + 1));
   OS::SNPrint(buffer, len + 1, format, message);
   Stop(buffer);
 }
 
 }  // namespace dart