Debugger: correctly ensure debug info in Debug::Break.

src/debug/debug.cc

Index: src/debug/debug.cc
diff --git a/src/debug/debug.cc b/src/debug/debug.cc
index 55837342eb9e9547ea300f6d331fbe519ddfc1b9..926c08390b6f2508724fd28d1e2525a717c3db20 100644
--- a/src/debug/debug.cc
+++ b/src/debug/debug.cc
@@ -580,8 +580,12 @@ void Debug::Break(Arguments args, JavaScriptFrame* frame) {
   PostponeInterruptsScope postpone(isolate_);
 
   // Get the debug info (create it if it does not exist).
-  Handle<SharedFunctionInfo> shared =
-      Handle<SharedFunctionInfo>(frame->function()->shared());
+  Handle<JSFunction> function(frame->function());
+  Handle<SharedFunctionInfo> shared(function->shared());
+  if (!EnsureDebugInfo(shared, function)) {
+    // Return if we failed to retrieve the debug info.
+    return;
+  }
   Handle<DebugInfo> debug_info(shared->GetDebugInfo());
 
   // Find the break point where execution has stopped.