Stop unwanted class finalization when using dart:io HttpClient from builtin.dart

runtime/vm/isolate.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_ISOLATE_H_
 #define VM_ISOLATE_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/thread.h"
@@ skipping 565 matching lines @@
   // Populate all deferred slots that contain boxes for double, mint, simd
   // values.
   void MaterializeDeferredBoxes();
 
   // Populate all slots containing references to objects which allocations
   // were eliminated by AllocationSinking pass.
   void MaterializeDeferredObjects();
 
   static char* GetStatus(const char* request);
 
+  intptr_t BlockClassFinalization() {
+    ASSERT(defer_finalization_count_ >= 0);
+    return defer_finalization_count_++;
+  }
+
+  intptr_t UnblockClassFinalization() {
+    ASSERT(defer_finalization_count_ > 0);
+    return defer_finalization_count_--;
+  }
+
+  bool AllowClassFinalization() {
+    ASSERT(defer_finalization_count_ >= 0);
+    return defer_finalization_count_ == 0;
+  }
+
  private:
   Isolate();
 
   void BuildName(const char* name_prefix);
   void PrintInvokedFunctions();
 
   static bool FetchStacktrace();
   static bool FetchStackFrameDetails();
   char* GetStatusDetails();
   char* GetStatusStacktrace();
@@ skipping 23 matching lines @@
   intptr_t deopt_id_;
   Mutex* mutex_;  // protects stack_limit_ and saved_stack_limit_.
   uword stack_limit_;
   uword saved_stack_limit_;
   MessageHandler* message_handler_;
   uword spawn_data_;
   bool is_runnable_;
   IsolateRunState running_state_;
   GcPrologueCallbacks gc_prologue_callbacks_;
   GcEpilogueCallbacks gc_epilogue_callbacks_;
+  intptr_t defer_finalization_count_;
 
   // Deoptimization support.
   intptr_t* deopt_cpu_registers_copy_;
   fpu_register_t* deopt_fpu_registers_copy_;
   intptr_t* deopt_frame_copy_;
   intptr_t deopt_frame_copy_size_;
   DeferredSlot* deferred_boxes_;
   DeferredSlot* deferred_object_refs_;
 
   intptr_t deferred_objects_count_;
@@ skipping 125 matching lines @@
 
  private:
   Isolate::IsolateRunState saved_state_;
 
   DISALLOW_COPY_AND_ASSIGN(IsolateRunStateManager);
 };
 
 }  // namespace dart
 
 #endif  // VM_ISOLATE_H_