Fix bad commit of stale patch set of original CL "Make NoReloadScope thread safe"

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 "include/dart_native_api.h"
 #include "platform/assert.h"
 #include "platform/text_buffer.h"
@@ skipping 130 matching lines @@
 NoOOBMessageScope::~NoOOBMessageScope() {
   thread()->RestoreOOBMessageInterrupts();
 }
 
 
 NoReloadScope::NoReloadScope(Isolate* isolate, Thread* thread)
     : StackResource(thread),
       isolate_(isolate) {
   ASSERT(isolate_ != NULL);
   AtomicOperations::FetchAndIncrement(&(isolate_->no_reload_scope_depth_));
+  ASSERT(
+      AtomicOperations::LoadRelaxed(&(isolate_->no_reload_scope_depth_)) >= 0);
 }
 
 
 NoReloadScope::~NoReloadScope() {
-  uintptr_t previous_value =
-      AtomicOperations::FetchAndDecrement(&(isolate_->no_reload_scope_depth_));
-  // If the previous value was 0 we have underflowed.
-  ASSERT(previous_value != 0);
+  AtomicOperations::FetchAndDecrement(&(isolate_->no_reload_scope_depth_));
+  ASSERT(
+      AtomicOperations::LoadRelaxed(&(isolate_->no_reload_scope_depth_)) >= 0);
 }
 
 
 void Isolate::RegisterClass(const Class& cls) {
   NOT_IN_PRODUCT(
     if (IsReloading()) {
       reload_context()->RegisterClass(cls);
       return;
     }
   )
@@ skipping 2726 matching lines @@
 void IsolateSpawnState::DecrementSpawnCount() {
   ASSERT(spawn_count_monitor_ != NULL);
   ASSERT(spawn_count_ != NULL);
   MonitorLocker ml(spawn_count_monitor_);
   ASSERT(*spawn_count_ > 0);
   *spawn_count_ = *spawn_count_ - 1;
   ml.Notify();
 }
 
 }  // namespace dart