Send deprecation messages for prefixed gradients now that it's possible.

third_party/WebKit/LayoutTests/fast/gradients/css3-color-stops.html

Index: third_party/WebKit/LayoutTests/fast/gradients/css3-color-stops.html
diff --git a/third_party/WebKit/LayoutTests/fast/gradients/css3-color-stops.html b/third_party/WebKit/LayoutTests/fast/gradients/css3-color-stops.html
index fd7ab8ced613d39f36dcd040b92727dbdeee59ec..0408f1caf0a037590219e998a09e978b6efe332f 100644
--- a/third_party/WebKit/LayoutTests/fast/gradients/css3-color-stops.html
+++ b/third_party/WebKit/LayoutTests/fast/gradients/css3-color-stops.html
@@ -13,50 +13,41 @@
     }
 
     .linear1 {
-      background-image: -webkit-linear-gradient(left, black);
-      background-image: -moz-linear-gradient(left, black);
+      background-image: linear-gradient(to right, black);
     }
 
     .linear2 {
-      background-image: -webkit-linear-gradient(left, white, black);
-      background-image: -moz-linear-gradient(left, white, black);
+      background-image: linear-gradient(to right, white, black);
     }
 
     .linear3 {
-      background-image: -webkit-linear-gradient(left, red, green, blue);
-      background-image: -moz-linear-gradient(left, red, green, blue);
+      background-image: linear-gradient(to right, red, green, blue);
     }
 
     .linear4 {
-      background-image: -webkit-linear-gradient(left, red 25%, green 50%, blue 75%);
-      background-image: -moz-linear-gradient(left, red 25%, green 50%, blue 75%);
+      background-image: linear-gradient(to right, red 25%, green 50%, blue 75%);
     }
 
     .linear5 {
       /* Green should get shifted to 50% */
-      background-image: -webkit-linear-gradient(left, red 50%, green 30%, blue 90%);
-      background-image: -moz-linear-gradient(left, red 50%, green 30%, blue 90%);
+      background-image: linear-gradient(to right, red 50%, green 30%, blue 90%);
     }
 
     .linear6 {
       /* Green and yellow should be evenly spaced */
-      background-image: -webkit-linear-gradient(left, red, yellow, green, blue);
-      background-image: -moz-linear-gradient(left, red, yellow, green, blue);
+      background-image: linear-gradient(to right, red, yellow, green, blue);
     }
 
     .linear7 {
-      background-image: -webkit-linear-gradient(red -50%, green, blue, green, blue 150%);
-      background-image: -moz-linear-gradient(red -50%, green, blue, green, blue 150%);
+      background-image: linear-gradient(red -50%, green, blue, green, blue 150%);
     }
 
     .linear8 {
-      background-image: -webkit-linear-gradient(left, red, green 100px, blue);
-      background-image: -moz-linear-gradient(left, red, green 100px, blue);
+      background-image: linear-gradient(to right, red, green 100px, blue);
     }
 
     .linear9 {
-      background-image: -webkit-linear-gradient(left, red, green 120%, blue);
-      background-image: -moz-linear-gradient(left, red, green 120%, blue);
+      background-image: linear-gradient(to right, red, green 120%, blue);
     }
   </style>
   <script type="text/javascript" charset="utf-8">