Redraw seems to work correctly on the Mac now, so only invalidate the shifted region like on other platforms.

git-svn-id: svn+ssh://src.earth.threerings.net/nenya/trunk@288 ed5b42cb-e716-0410-a449-f6a68f950b19

src/java/com/threerings/media/VirtualMediaPanel.java

@@ -241,12 +241,6 @@ public class VirtualMediaPanel extends MediaPanel
 //                      "), d=(" + dx + ", " + dy +
 //                      "), width=" + width + ", height=" + height + "].");
 
-
-            // Mac OS X's redraw breaks on scrolling, so we repaint the
-            // entire panel 
-            if (RunAnywhere.isMacOS()) {
-                _metamgr.getRegionManager().invalidateRegion(_nx, _ny, width, height);
-            } else {
             _dx = dx;
             _dy = dy;
 
@@ -267,7 +261,6 @@ public class VirtualMediaPanel extends MediaPanel
             } else if (dx < 0) {
                 _metamgr.getRegionManager().invalidateRegion(_nx, sy, -dx, shei);
             }
-            }
 
 
             // now go ahead and update our location so that changes in