Fixes #1034 - Check for style.removeAttribute before calling it

Fixes issue in non IE browsers that happen to come down this path

src/css.js

@@ -534,7 +534,8 @@ if ( !jQuery.support.opacity ) {
 			style.zoom = 1;
 
 			// if setting opacity to 1, and no other filters exist - attempt to remove filter attribute #6652
-			if ( value >= 1 && jQuery.trim( filter.replace( ralpha, "" ) ) === "" ) {
+			if ( value >= 1 && jQuery.trim( filter.replace( ralpha, "" ) ) === "" &&
+				style.removeAttribute ) {
 
 				// Setting style.filter to null, "" & " " still leave "filter:" in the cssText
 				// if "filter:" is present at all, clearType is disabled, we want to avoid this