Remove all usage of -webkit-*gradient inside blink

Tools/GardeningServer/styles/common.css

Index: Tools/GardeningServer/styles/common.css
diff --git a/Tools/GardeningServer/styles/common.css b/Tools/GardeningServer/styles/common.css
index 9f7e8c081df679e818540d5f43b7ad86b8039eea..be0f21824445f6536bb91dd5486c2ce4bc5824b8 100644
--- a/Tools/GardeningServer/styles/common.css
+++ b/Tools/GardeningServer/styles/common.css
@@ -44,7 +44,7 @@ a {
 .ui-widget button, button {
     font-family: 'Open Sans';
     border-radius: 2px;
-    background-image: -webkit-linear-gradient(top,#f5f5f5,#f1f1f1);
+    background-image: linear-gradient(#f5f5f5, #f1f1f1);
     border: 1px solid rgba(0, 0, 0, 0.1);
     border-radius: 2px;
     color: #666;
@@ -71,7 +71,7 @@ button[disabled] {
 }
 
 button:hover {
-    background-image: -webkit-linear-gradient(top,#f8f8f8,#f1f1f1);
+    background-image: linear-gradient(#f8f8f8, #f1f1f1);
     -webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.1);
     background-color: #f8f8f8;
     background-image: linear-gradient(top,#f8f8f8,#f1f1f1);
@@ -88,7 +88,7 @@ button:focus {
 button.default {
     border: 1px solid #3079ED;
     color: white;
-    background-image: -webkit-linear-gradient(top,#4d90fe,#4787ed);
+    background-image: linear-gradient(#4d90fe, #4787ed);
 }
 
 button.default:hover {