Unprefix usage of -webkit-transform in tests

LayoutTests/animations/animation-offscreen-to-onscreen.html

Index: LayoutTests/animations/animation-offscreen-to-onscreen.html
diff --git a/LayoutTests/animations/animation-offscreen-to-onscreen.html b/LayoutTests/animations/animation-offscreen-to-onscreen.html
index f0665dc1b9c53e2163990c88d8c01325afb0bfd4..6f681968ab0a65b9e0af75bcdbd90c8a5d8d039e 100644
--- a/LayoutTests/animations/animation-offscreen-to-onscreen.html
+++ b/LayoutTests/animations/animation-offscreen-to-onscreen.html
@@ -13,15 +13,15 @@
       width: 100px;
       margin: 0;
       background-color: green;
-      -webkit-transform: translate(-2000px, 0px);
+      transform: translate(-2000px, 0px);
       -webkit-animation-duration: 1s;
       -webkit-animation-direction: normal;
       -webkit-animation-timing-function: linear;
       -webkit-animation-name: "anim";
     }
     @-webkit-keyframes "anim" {
-        0% { -webkit-transform: translate(100px, 0px); }
-      100% { -webkit-transform: translate(100px, 0px); }
+        0% { transform: translate(100px, 0px); }
+      100% { transform: translate(100px, 0px); }
     }
   </style>
   <script src="resources/animation-test-helpers.js" type="text/javascript"></script>