Refactor Win panel mouse watcher to use PanelMouseWatcher base class.

chrome/browser/ui/panels/panel_browsertest.cc

Index: chrome/browser/ui/panels/panel_browsertest.cc
===================================================================
--- chrome/browser/ui/panels/panel_browsertest.cc	(revision 102599)
+++ chrome/browser/ui/panels/panel_browsertest.cc	(working copy)
@@ -827,12 +827,12 @@
 }
 #endif
 
-#if defined(TOOLKIT_GTK) || defined(OS_MACOSX)
+// TODO(jennb): Disabling for Windows due to failure on XP and Vista.
+#if defined(OS_WIN)
+#define MAYBE_MinimizeRestore DISABLED_MinimizeRestore
+#else
 #define MAYBE_MinimizeRestore MinimizeRestore
-#else
-#define MAYBE_MinimizeRestore DISABLED_MinimizeRestore
 #endif
-
 IN_PROC_BROWSER_TEST_F(PanelBrowserTest, MAYBE_MinimizeRestore) {
   // Disable mouse watcher.  We'll simulate mouse movements for test.
   NativePanelTesting::GetPanelMouseWatcherInstance()->EnableTestingMode();