Update V8 to r6190 as required by WebKit r75315

Change-Id: I0b2f598e4d8748df417ad350fc47a1c465ad1fef
diff --git a/src/d8-debug.cc b/src/d8-debug.cc
index 5f3ed76..8a3886c 100644
--- a/src/d8-debug.cc
+++ b/src/d8-debug.cc
@@ -34,12 +34,21 @@
 
 namespace v8 {
 
-void PrintPrompt() {
-  printf("dbg> ");
+static bool was_running = true;
+
+void PrintPrompt(bool is_running) {
+  const char* prompt = is_running? "> " : "dbg> ";
+  was_running = is_running;
+  printf("%s", prompt);
   fflush(stdout);
 }
 
 
+void PrintPrompt() {
+  PrintPrompt(was_running);
+}
+
+
 void HandleDebugEvent(DebugEvent event,
                       Handle<Object> exec_state,
                       Handle<Object> event_data,
@@ -91,7 +100,7 @@
   bool running = false;
   while (!running) {
     char command[kBufferSize];
-    PrintPrompt();
+    PrintPrompt(running);
     char* str = fgets(command, kBufferSize, stdin);
     if (str == NULL) break;
 
@@ -284,7 +293,9 @@
   } else {
     printf("???\n");
   }
-  PrintPrompt();
+
+  bool is_running = details->Get(String::New("running"))->ToBoolean()->Value();
+  PrintPrompt(is_running);
 }