Fix wrong state of IsolateInBackgroundNotification and IsolateInForegroundNotification.

src/isolate.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/isolate.h"
 
 #include <stdlib.h>
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
@@ skipping 3156 matching lines @@
 }
 
 void Isolate::SetRAILMode(RAILMode rail_mode) {
   rail_mode_.SetValue(rail_mode);
   if (FLAG_trace_rail) {
     PrintIsolate(this, "RAIL mode: %s\n", RAILModeName(rail_mode));
   }
 }
 
 void Isolate::IsolateInBackgroundNotification() {
-  is_isolate_in_background_ = false;
+  is_isolate_in_background_ = true;
   heap()->ActivateMemoryReducerIfNeeded();
 }
 
 void Isolate::IsolateInForegroundNotification() {
-  is_isolate_in_background_ = true;
+  is_isolate_in_background_ = false;
 }
 
 bool StackLimitCheck::JsHasOverflowed(uintptr_t gap) const {
   StackGuard* stack_guard = isolate_->stack_guard();
 #ifdef USE_SIMULATOR
   // The simulator uses a separate JS stack.
   Address jssp_address = Simulator::current(isolate_)->get_sp();
   uintptr_t jssp = reinterpret_cast<uintptr_t>(jssp_address);
   if (jssp - gap < stack_guard->real_jslimit()) return true;
 #endif  // USE_SIMULATOR
@@ skipping 12 matching lines @@
   // Then check whether this scope intercepts.
   if ((flag & intercept_mask_)) {
     intercepted_flags_ |= flag;
     return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8