Remove the barely used macro assemblers after merging their contents to the base

runtime/vm/isolate.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/isolate.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "lib/mirrors.h"
 #include "vm/code_observers.h"
@@ skipping 370 matching lines @@
 // TODO(5411455): Use flag to override default value and Validate the
 // stack size by querying OS.
 uword Isolate::GetSpecifiedStackSize() {
   ASSERT(Isolate::kStackSizeBuffer < Thread::GetMaxStackSize());
   uword stack_size = Thread::GetMaxStackSize() - Isolate::kStackSizeBuffer;
   return stack_size;
 }
 
 
 void Isolate::SetStackLimitFromCurrentTOS(uword stack_top_value) {
-#ifdef USING_SIMULATOR
+#if defined(USING_SIMULATOR)
   // Ignore passed-in native stack top and use Simulator stack top.
   Simulator* sim = Simulator::Current();  // May allocate a simulator.
   ASSERT(simulator() == sim);  // This isolate's simulator is the current one.
   stack_top_value = sim->StackTop();
   // The overflow area is accounted for by the simulator.
 #endif
   SetStackLimit(stack_top_value - GetSpecifiedStackSize());
 }
 
 
@@ skipping 283 matching lines @@
                       isolate->saved_stack_limit(),
                       heap->Used(Heap::kNew) / KB,
                       heap->Capacity(Heap::kNew) / KB,
                       heap->Used(Heap::kOld) / KB,
                       heap->Capacity(Heap::kOld) / KB);
   ASSERT(n < 256);
   return strdup(buffer);
 }
 
 }  // namespace dart