Fix for the painting problem with drop down scroll bar

third_party/WebKit/WebCore/platform/chromium/PopupMenuChromium.cpp

 // Copyright (c) 2008, Google Inc.
 // All rights reserved.
 // 
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 // 
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
@@ skipping 67 matching lines @@
     virtual void paint(GraphicsContext* gc, const IntRect& rect);
     virtual bool handleMouseDownEvent(const PlatformMouseEvent& event);
     virtual bool handleMouseMoveEvent(const PlatformMouseEvent& event);
     virtual bool handleMouseReleaseEvent(const PlatformMouseEvent& event);
     virtual bool handleWheelEvent(const PlatformWheelEvent& event);
     virtual bool handleKeyEvent(const PlatformKeyboardEvent& event);
 
     // ScrollView
     virtual HostWindow* hostWindow() const;
 
+    // Widget
+    virtual void invalidateRect(const IntRect&);
+
     // PopupListBox methods
 
     // Show the popup
     void showPopup();
 
     // Hide the popup.  Do not call this directly: use client->hidePopup().
     void hidePopup();
 
     // Update our internal list to match the client.
     void updateFromElement();
@@ skipping 549 matching lines @@
     return true;
 }
 
 HostWindow* PopupListBox::hostWindow() const
 {
     // Our parent is the root ScrollView, so it is the one that has a
     // HostWindow.  FrameView::hostWindow() works similarly.
     return parent() ? parent()->hostWindow() : 0;
 }
 
+void PopupListBox::invalidateRect(const IntRect& rect)
+{
+    // Since we are returning the HostWindow of our parent as our own in
+    // hostWindow(), we need to invalidate in our parent coordinates.
+    IntRect newRect(rect);
+    newRect.move(kBorderSize, kBorderSize);
+    FramelessScrollView::invalidateRect(newRect);
+}
+
 // From HTMLSelectElement.cpp
 static String stripLeadingWhiteSpace(const String& string)
 {
     int length = string.length();
     int i;
     for (i = 0; i < length; ++i)
         if (string[i] != noBreakSpace &&
             (string[i] <= 0x7F ? !isspace(string[i]) : (direction(string[i]) != WhiteSpaceNeutral)))
             break;
 
@@ skipping 436 matching lines @@
 {
     p.m_popup->listBox()->updateFromElement();
 }
 
 bool PopupMenu::itemWritingDirectionIsNatural() 
 { 
     return false; 
 }
 
 } // namespace WebCore