RT-15096: IAE when pressing spacebar in TextArea

diff -r 39481ba13918 -r 2c60320ad6ee javafx-ui-controls/src/com/sun/javafx/scene/control/skin/TextAreaSkin.java
--- a/javafx-ui-controls/src/com/sun/javafx/scene/control/skin/TextAreaSkin.java	Fri Sep 02 18:13:06 2011 +0100
+++ b/javafx-ui-controls/src/com/sun/javafx/scene/control/skin/TextAreaSkin.java	Fri Sep 02 13:35:27 2011 -0700
@@ -636,7 +636,7 @@
             width = 0;
         }
 
-        return new Rectangle2D(x, y, width, height);
+        return (width >= 0 && height >= 0) ? new Rectangle2D(x, y, width, height) : null;
     }
 
     @Override public void scrollCharacterToVisible(final int index) {
@@ -651,7 +651,9 @@
                     return;
                 }
                 Rectangle2D characterBounds = getCharacterBounds(index);
-                scrollBoundsToVisible(characterBounds);
+                if (characterBounds != null) {
+                    scrollBoundsToVisible(characterBounds);
+                }
             }
         });
     }