Implement stack trace printing callback for v8

gin/public/v8_platform.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef GIN_PUBLIC_V8_PLATFORM_H_
 #define GIN_PUBLIC_V8_PLATFORM_H_
 
 #include "base/compiler_specific.h"
 #include "base/lazy_instance.h"
 #include "base/macros.h"
@@ skipping 35 matching lines @@
       const uint8_t* arg_types,
       const uint64_t* arg_values,
       std::unique_ptr<v8::ConvertableToTraceFormat>* arg_convertibles,
       unsigned int flags) override;
   void UpdateTraceEventDuration(const uint8_t* category_enabled_flag,
                                 const char* name,
                                 uint64_t handle) override;
 
   void AddTraceStateObserver(v8::Platform::TraceStateObserver*) override;
   void RemoveTraceStateObserver(v8::Platform::TraceStateObserver*) override;
+  StackTracePrinter GetStackTracePrinter() override;
 
  private:
   friend struct base::LazyInstanceTraitsBase<V8Platform>;
 
   V8Platform();
   ~V8Platform() override;
 
   DISALLOW_COPY_AND_ASSIGN(V8Platform);
 };
 
 }  // namespace gin
 
 #endif  // GIN_PUBLIC_V8_PLATFORM_H_