V8_Fatal now prints C++ stack trace in debug mode.

src/isolate.cc

Index: src/isolate.cc
diff --git a/src/isolate.cc b/src/isolate.cc
index b760aebf07d549ef367e1bc063333606ca3ff569..7c06903ea917b14f75ec6288b5be4ec0b8f3403f 100644
--- a/src/isolate.cc
+++ b/src/isolate.cc
@@ -812,7 +812,7 @@ static void PrintFrames(StringStream* accumulator,
 void Isolate::PrintStack(StringStream* accumulator) {
   if (!IsInitialized()) {
     accumulator->Add(
-        "\n==== Stack trace is not available ==========================\n\n");
+        "\n==== JS stack trace is not available =======================\n\n");
     accumulator->Add(
         "\n==== Isolate for the thread is not initialized =============\n\n");
     return;
@@ -825,7 +825,7 @@ void Isolate::PrintStack(StringStream* accumulator) {
   if (c_entry_fp(thread_local_top()) == 0) return;
 
   accumulator->Add(
-      "\n==== Stack trace ============================================\n\n");
+      "\n==== JS stack trace =========================================\n\n");
   PrintFrames(accumulator, StackFrame::OVERVIEW);
 
   accumulator->Add(