Fixed grab interaction with Windows Classic theme Testing: * For each theme in Windows 7, Windows 7 Basic, and Windows 7 Classic: - Ran testsprite2 - Pressed Ctrl-G to grab the mouse - Alt-tabbed away, verified mouse is no longer grabbed - Alt-tabbed back, verified that mouse was grabbed - Alt-tabbed away - Clicked in the window, verified mouse was grabbed - Alt-tabbed away - Grabbed the title bar and dragged the window around successfully, verified that mouse was grabbed when move modal loop completed - Alt-tabbed away - Clicked the minimize button on the title bar, the window was successfully minimized - Clicked on the icon in the task bar, the window was restored and the mouse grabbed again - Alt-tabbed away - Clicked the close button on the title bar, the window was successfully closed