Implement stack trace printing callback for v8

gin/v8_platform.cc

Index: gin/v8_platform.cc
diff --git a/gin/v8_platform.cc b/gin/v8_platform.cc
index 276dd77c9d64f2dd941b9613839f1941a041d326..dc887c43c3e0d242f8e599c1e3be96cd35eafda7 100644
--- a/gin/v8_platform.cc
+++ b/gin/v8_platform.cc
@@ -5,6 +5,7 @@
 #include "gin/public/v8_platform.h"
 
 #include "base/bind.h"
+#include "base/debug/stack_trace.h"
 #include "base/location.h"
 #include "base/sys_info.h"
 #include "base/threading/worker_pool.h"
@@ -42,6 +43,11 @@ class IdleTaskWithLocker : public v8::IdleTask {
   DISALLOW_COPY_AND_ASSIGN(IdleTaskWithLocker);
 };
 
+void PrintStackTrace() {
+  base::debug::StackTrace trace;
+  trace.Print();
+}
+
 }  // namespace
 
 // static
@@ -263,4 +269,8 @@ void V8Platform::RemoveTraceStateObserver(
   g_trace_state_dispatcher.Get().RemoveObserver(observer);
 }
 
+v8::Platform::StackTracePrinter V8Platform::GetStackTracePrinter() {
+  return PrintStackTrace;
+}
+
 }  // namespace gin