Move the canonical empty context to the VM isolate.

runtime/vm/flow_graph_compiler_mips.cc

 // Copyright (c) 2013, 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/globals.h"  // Needed here to get TARGET_ARCH_MIPS.
 #if defined(TARGET_ARCH_MIPS)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/ast_printer.h"
@@ skipping 1048 matching lines @@
         parsed_function().current_context_var()->index();
     if (num_locals > 1) {
       __ LoadObject(V0, Object::null_object());
     }
     for (intptr_t i = 0; i < num_locals; ++i) {
       // Subtract index i (locals lie at lower addresses than FP).
       if (((slot_base - i) == context_index)) {
         if (function.IsClosureFunction()) {
           __ sw(CTX, Address(FP, (slot_base - i) * kWordSize));
         } else {
-          const Context& empty_context = Context::ZoneHandle(
-              zone(), isolate()->object_store()->empty_context());
-          __ LoadObject(V1, empty_context);
+          __ LoadObject(V1, Object::empty_context());
           __ sw(V1, Address(FP, (slot_base - i) * kWordSize));
         }
       } else {
         ASSERT(num_locals > 1);
         __ sw(V0, Address(FP, (slot_base - i) * kWordSize));
       }
     }
   }
 
   EndCodeSourceRange(TokenPosition::kDartCodePrologue);
@@ skipping 784 matching lines @@
   __ AddImmediate(SP, kDoubleSize);
 }
 
 
 #undef __
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS