Revert "Don't add webkit prefix to SVG filters"

This reverts commit c746ae3.

Author: ai

lib/hacks/filter.coffee

@@ -6,9 +6,7 @@ class Filter extends Declaration
   # Check is it Internet Explorer filter
   check: (decl) ->
     v = decl.value
-
     v.toLowerCase().indexOf('alpha(') == -1 and
-      v.indexOf('DXImageTransform.Microsoft') == -1 and
-      v.indexOf('url(') == -1
+      v.indexOf('DXImageTransform.Microsoft') == -1
 
 module.exports = Filter

test/cases/filter.css

@@ -1,19 +1,15 @@
 a {
-    filter: blur(10px)
+    filter: blur(10px);
 }
 
 div {
-    filter: progid:DXImageTransform.Microsoft.Alpha(opacity=50)
+    filter: progid:DXImageTransform.Microsoft.Alpha(opacity=50);
 }
 
 b {
-    filter: alpha(opacity=100)
+    filter: alpha(opacity=100);
 }
 
 em {
-    filter: Alpha(opacity=100)
-}
-
-li {
-    filter: url(filters.svg#blur)
+    filter: Alpha(opacity=100);
 }

test/cases/filter.out.css

@@ -1,20 +1,16 @@
 a {
     -webkit-filter: blur(10px);
-            filter: blur(10px)
+            filter: blur(10px);
 }
 
 div {
-    filter: progid:DXImageTransform.Microsoft.Alpha(opacity=50)
+    filter: progid:DXImageTransform.Microsoft.Alpha(opacity=50);
 }
 
 b {
-    filter: alpha(opacity=100)
+    filter: alpha(opacity=100);
 }
 
 em {
-    filter: Alpha(opacity=100)
-}
-
-li {
-    filter: url(filters.svg#blur)
+    filter: Alpha(opacity=100);
 }