Add Mouse hover behavior to Mac Panels when minimized

ui/gfx/screen_mac.mm

Index: ui/gfx/screen_mac.mm
diff --git a/ui/gfx/screen_mac.mm b/ui/gfx/screen_mac.mm
new file mode 100644
index 0000000000000000000000000000000000000000..b38344ac76b85d9217aa67efbcaf663b94f08103
--- /dev/null
+++ b/ui/gfx/screen_mac.mm
@@ -0,0 +1,20 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/gfx/screen.h"
+
+#import <Cocoa/Cocoa.h>
+
+namespace gfx {
+
+// static
+gfx::Point Screen::GetCursorScreenPoint() {
+  NSPoint mouseLocation  = [NSEvent mouseLocation];
+  // Flip coordinates to gfx (0,0 in top-left corner) using primary screen.
+  NSScreen* screen = [[NSScreen screens] objectAtIndex:0];
+  mouseLocation.y = NSMaxY([screen frame]) - mouseLocation.y;
+  return gfx::Point(mouseLocation.x, mouseLocation.y);
+}
+
+}  // namespace gfx