Refactor [FramedBrowserWindow drawWindowThemeInDirtyRect:] to use themeImagePositionForAlignment:

chrome/browser/ui/cocoa/floating_bar_backing_view.mm

Index: chrome/browser/ui/cocoa/floating_bar_backing_view.mm
diff --git a/chrome/browser/ui/cocoa/floating_bar_backing_view.mm b/chrome/browser/ui/cocoa/floating_bar_backing_view.mm
index fef660b8de94a23cfea52a69f884e9834150a1e7..7f626f4a47152f4c55fc95ad1a8b85674025ecae 100644
--- a/chrome/browser/ui/cocoa/floating_bar_backing_view.mm
+++ b/chrome/browser/ui/cocoa/floating_bar_backing_view.mm
@@ -19,11 +19,9 @@
     [[NSColor windowBackgroundColor] set];
   NSRectFill(rect);
 
-  // TODO(rohitrao): Don't assume -22 here.
   [FramedBrowserWindow drawWindowThemeInDirtyRect:rect
                                           forView:self
                                            bounds:[self bounds]
-                                           offset:NSMakePoint(0, -22)
                              forceBlackBackground:YES];
 
 }