Update paper-checkbox to 0.5.4.

third_party/polymer/components-chromium/paper-checkbox/paper-checkbox.css

 /*
 Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
 This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
 The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
 The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
 Code distributed by Google as part of the polymer project is also
 subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
 */
 
 :host {
   display: inline-block;
   white-space: nowrap;
 }
 
 :host(:focus) {
   outline: 0;
 }
 
+.hidden {
+  display: none;
+}
+
 #checkboxContainer {
   position: relative;
   width: 18px;
   height: 18px;
   cursor: pointer;
   -webkit-transform: translateZ(0);
   transform: translateZ(0);
 }
 
 #checkboxContainer.labeled {
   display: inline-block;
   vertical-align: middle;
 }
 
 #ink {
   position: absolute;
   top: -15px;
   left: -15px;
   width: 48px;
   height: 48px;
   color: #5a5f5a;
 }
 
 #ink[checked] {
-  color: #0f9d58;
+  color: #B2DFDB;
 }
 
 #checkbox {
-  position: absolute;
+  position: relative;
   box-sizing: border-box;
-  top: 0px;
-  left: 0px; 
-  width: 18px;
-  height: 18px;
-  border: solid 2px;
-  border-color: #5a5a5a;
+  height: 100%;
+  border: solid 2px #5a5a5a;
+  border-radius: 2px;
   pointer-events: none;
+  -webkit-transition: background-color 140ms, border-color 140ms;
+  transition: background-color 140ms, border-color 140ms;
 }
 
 /* checkbox checked animations */
-#checkbox.checked.box {
-  border: solid 2px;
-  -webkit-animation: box-shrink 140ms ease-out forwards;
-  animation: box-shrink 140ms ease-out forwards;
-}
-
-@-webkit-keyframes box-shrink {
-  0% {
-    -webkit-transform: rotate(0deg);
-    top: 0px;
-    left: 0px;
-    width: 18px;
-    height: 18px;
-  }
-  100% {
-    -webkit-transform: rotate(45deg);
-    top: 13px;
-    left: 5px;
-    width: 4px;
-    height: 4px;
-  }
-}
-
-@keyframes box-shrink {
-  0% {
-    transform: rotate(0deg);
-    top: 0px;
-    left: 0px;
-    width: 18px;
-    height: 18px;
-  }
-  100% {
-    transform: rotate(45deg);
-    top: 13px;
-    left: 5px;
-    width: 4px;
-    height: 4px;
-  }
-}
-
-#checkbox.checked.checkmark {
-  border-left: none;
-  border-top: none;
+:host([checked]) #checkmark {
   -webkit-animation: checkmark-expand 140ms ease-out forwards;
   animation: checkmark-expand 140ms ease-out forwards;
 }
 
 @-webkit-keyframes checkmark-expand {
   0% {
-    -webkit-transform: rotate(45deg);
-    top: 13px;
-    left: 5px;
-    width: 4px;
-    height: 4px;
+    top: 9px;
+    left: 6px;
+    width: 0px;
+    height: 0px;
   }
   100% {
-    -webkit-transform: rotate(45deg);
-    top: -4px;
-    left: 6px; 
-    width: 10px;
-    height: 21px;
-    border-right-width: 2px;
-    border-bottom-width: 2px;
+    top: -1px;
+    left: 4px;
+    width: 5px;
+    height: 10px;
   }
 }
 
 @keyframes checkmark-expand {
   0% {
-    transform: rotate(45deg);
-    top: 13px;
-    left: 5px;
-    width: 4px;
-    height: 4px;
+    top: 9px;
+    left: 6px;
+    width: 0px;
+    height: 0px;
   }
   100% {
-    transform: rotate(45deg);
-    top: -4px;
-    left: 6px; 
-    width: 10px;
-    height: 21px;
-    border-right-width: 2px;
-    border-bottom-width: 2px;
+    top: -1px;
+    left: 4px;
+    width: 5px;
+    height: 10px;
   }
 }
 
 #checkbox.checked {
+  background-color: #009688;
+  border-color: #009688;
+}
+
+#checkmark {
   -webkit-transform: rotate(45deg);
   transform: rotate(45deg);
-  top: -4px;
-  left: 6px;
-  width: 10px;
-  height: 21px;
+  position: absolute;
+  top: -1px;
+  left: 4px;
+  width: 5px;
+  height: 10px;
+  border-style: solid;
   border-top: none;
   border-left: none;
   border-right-width: 2px;
   border-bottom-width: 2px;
-  border-color: #0f9d58;
-}
-
-/* checkbox unchecked animations */
-#checkbox.unchecked.checkmark {
-  -webkit-transform: rotate(45deg);
-  transform: rotate(45deg);
-  border-left: none;
-  border-top: none;
-  -webkit-animation: checkmark-shrink 140ms ease-out forwards;
-  animation: checkmark-shrink 140ms ease-out forwards;
-}
-
-@-webkit-keyframes checkmark-shrink {
-  0% {
-    top: -4px;
-    left: 6px; 
-    width: 10px;
-    height: 21px;
-    border-right-width: 2px;
-    border-bottom-width: 2px;
-  }
-  100% {
-    top: 13px;
-    left: 5px;
-    width: 4px;
-    height: 4px;
-  }
-}
-
-@keyframes checkmark-shrink {
-  0% {
-    top: -4px;
-    left: 6px; 
-    width: 10px;
-    height: 21px;
-    border-right-width: 2px;
-    border-bottom-width: 2px;
-  }
-  100% {
-    top: 13px;
-    left: 5px;
-    width: 4px;
-    height: 4px;
-  }
-}
-
-#checkbox.unchecked.box {
-  -webkit-animation: box-expand 140ms ease-out forwards;
-  animation: box-expand 140ms ease-out forwards;
-}
-
-@-webkit-keyframes box-expand {
-  0% {
-    -webkit-transform: rotate(45deg);
-    top: 13px;
-    left: 5px;
-    width: 4px;
-    height: 4px;
-  }
-  100% {
-    -webkit-transform: rotate(0deg);
-    top: 0px;
-    left: 0px;
-    width: 18px;
-    height: 18px;
-  }
-}
-
-@keyframes box-expand {
-  0% {
-    transform: rotate(45deg);
-    top: 13px;
-    left: 5px;
-    width: 4px;
-    height: 4px;
-  }
-  100% {
-    transform: rotate(0deg);
-    top: 0px;
-    left: 0px;
-    width: 18px;
-    height: 18px;
-  }
+  border-color: white;
 }
 
 /* label */
 #checkboxLabel {
   position: relative;
   display: inline-block;
   vertical-align: middle;
   padding-left: 8px;
   white-space: normal;
   pointer-events: none;
 }
 
 #checkboxLabel[hidden] {
   display: none;
 }
 
 /* disabled state */
 :host([disabled]) {
   pointer-events: none;
 }
 
 :host([disabled]) #checkbox {
   opacity: 0.33;
   border-color: #5a5a5a;
 }
+
+:host([disabled][checked]) #checkbox {
+  background-color: #5a5a5a;
+}