CSS Animations: Remove unnecessary webkit prefixes from layout tests

third_party/WebKit/LayoutTests/animations/keyframes.html

Index: third_party/WebKit/LayoutTests/animations/keyframes.html
diff --git a/third_party/WebKit/LayoutTests/animations/keyframes.html b/third_party/WebKit/LayoutTests/animations/keyframes.html
index 256c61ee78c599b2c6f01a5bfc0947e1a89d07a3..a2dbe60b5ac2ee520211b8f8bc89cedde5cdca91 100644
--- a/third_party/WebKit/LayoutTests/animations/keyframes.html
+++ b/third_party/WebKit/LayoutTests/animations/keyframes.html
@@ -13,11 +13,11 @@
         height: 100px;
         width: 100px;
         background-color: blue;
-        -webkit-animation-duration: 1s;
-        -webkit-animation-timing-function: linear;
-        -webkit-animation-name: anim;
+        animation-duration: 1s;
+        animation-timing-function: linear;
+        animation-name: anim;
     }
-    @-webkit-keyframes anim {
+    @keyframes anim {
         from { left: 50px; }
         20%  { left: 100px; }
         40%  { left: 100px; }