Use a block cursor in overtype mode

Source/core/testing/Internals.cpp

Index: Source/core/testing/Internals.cpp
diff --git a/Source/core/testing/Internals.cpp b/Source/core/testing/Internals.cpp
index 30b25aee9548fa2bdcfbbda3b514e7ec8c6feb3c..b3ad2178f7a69fb75bb39f57ee47f9d9055f8d2a 100644
--- a/Source/core/testing/Internals.cpp
+++ b/Source/core/testing/Internals.cpp
@@ -1895,6 +1895,17 @@ void Internals::initializeMockCDM()
 }
 #endif
 
+PassRefPtr<ClientRect> Internals::selectionBounds(ExceptionCode& ec)
+{
+    Document* document = contextDocument();
+    if (!document || !document->frame() || !document->frame()->selection()) {
+        ec = INVALID_ACCESS_ERR;
+        return 0;
+    }
+
+    return ClientRect::create(document->frame()->selection()->bounds());
+}
+
 String Internals::markerTextForListItem(Element* element, ExceptionCode& ec)
 {
     if (!element) {