Fix shutdown races and move signal blocking into profiler

runtime/vm/profiler.h

 // 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.
 
 #ifndef VM_PROFILER_H_
 #define VM_PROFILER_H_
 
 #include "platform/hashmap.h"
 #include "platform/thread.h"
 #include "vm/allocation.h"
 #include "vm/code_observers.h"
 #include "vm/globals.h"
 
 namespace dart {
 
 // Forward declarations.
 class JSONStream;
 
 // Profiler manager.
 class ProfilerManager : public AllStatic {
  public:
   static void InitOnce();
   static void Shutdown();
 
   static void SetupIsolateForProfiling(Isolate* isolate);
   static void ShutdownIsolateForProfiling(Isolate* isolate);
-  static void ScheduleIsolate(Isolate* isolate);
+  static void ScheduleIsolate(Isolate* isolate, bool inside_signal = false);
   static void DescheduleIsolate(Isolate* isolate);
 
   static void PrintToJSONStream(Isolate* isolate, JSONStream* stream);
 
   static void WriteTracing(Isolate* isolate, const char* name, Dart_Port port);
 
  private:
   static const intptr_t kMaxProfiledIsolates = 4096;
   static bool initialized_;
   static bool shutdown_;
@@ skipping 152 matching lines @@
   const uintptr_t original_pc_;
   const uintptr_t original_fp_;
   const uintptr_t original_sp_;
   uintptr_t lower_bound_;
 };
 
 
 }  // namespace dart
 
 #endif  // VM_PROFILER_H_