Media Router: Replace sink custom elements with core/paper elements.

chrome/browser/resources/media_router/elements/media_router_container/media_router_container.css

Index: chrome/browser/resources/media_router/elements/media_router_container/media_router_container.css
diff --git a/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.css b/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.css
index 93dabb009703d79f4cedd4bb55ef9a73d3fe89a4..35b4da08574c69a813b8219c55353f320a9c560e 100644
--- a/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.css
+++ b/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.css
@@ -5,6 +5,7 @@
 #cast-modes {
   margin: 30px 0;
   position: absolute;
+  z-index: 1;
 }
 
 :host-context(html[dir='ltr']) #cast-modes {
@@ -39,6 +40,10 @@
   display: none;
 }
 
+.route {
+  color: rgb(119, 119, 119);
+}
+
 #router-header-text {
   -webkit-padding-start: 20px;
   flex-grow: 1;
@@ -49,7 +54,23 @@
   padding-top: 10px;
 }
 
-#sinks {
+.sink {
+  -webkit-user-select: none;
+  cursor: pointer;
+  font-size: 1.0em;
+}
+
+.sink:hover {
+  background-color: rgb(187, 206, 236);
+  border: 0;
+}
+
+.sink-icon {
+  -webkit-padding-end: 10px;
+}
+
+#sink-list {
+  margin: 0;
   max-height: 275px;
   overflow-y: scroll;
 }
@@ -59,4 +80,5 @@
   height: 100%;
   position: absolute;
   width: 100%;
+  z-index: 1;
 }