LocalWindow::printErrorMessage(): check if frame is available.

Source/core/frame/LocalDOMWindow.cpp

Index: Source/core/frame/LocalDOMWindow.cpp
diff --git a/Source/core/frame/LocalDOMWindow.cpp b/Source/core/frame/LocalDOMWindow.cpp
index 69b6c0f1055157c96e22825394f4d555fb71b287..06712ca93f0ea358d5e220ca01134358fe060250 100644
--- a/Source/core/frame/LocalDOMWindow.cpp
+++ b/Source/core/frame/LocalDOMWindow.cpp
@@ -1725,6 +1725,9 @@ void LocalDOMWindow::setLocation(const String& urlString, LocalDOMWindow* callin
 
 void LocalDOMWindow::printErrorMessage(const String& message)
 {
+    if (!isCurrentlyDisplayedInFrame())
+        return;
+
     if (message.isEmpty())
         return;