MD Settings: Remove usage of deprecated iron-flex-layout.html, for CrOS.

ui/webui/resources/cr_elements/network/cr_network_icon.html

Index: ui/webui/resources/cr_elements/network/cr_network_icon.html
diff --git a/ui/webui/resources/cr_elements/network/cr_network_icon.html b/ui/webui/resources/cr_elements/network/cr_network_icon.html
index 9158262b0c2ffd5b8ff766a8705a49935aeb2f38..9936f489268da9cc0547ae971cd0d46b570eed0f 100644
--- a/ui/webui/resources/cr_elements/network/cr_network_icon.html
+++ b/ui/webui/resources/cr_elements/network/cr_network_icon.html
@@ -2,10 +2,11 @@
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icon/iron-icon.html">
 <link rel="import" href="chrome://resources/cr_elements/network/cr_onc_types.html">
 <link rel="import" href="chrome://resources/cr_elements/network/network_icons.html">
+<link rel="import" href="chrome://resources/cr_elements/hidden_style_css.html">
 
 <dom-module id="cr-network-icon">
   <template>
-    <style>
+    <style include="cr-hidden-style">
       :host {
         display: inline-flex;
         overflow: hidden;
@@ -13,11 +14,6 @@
         position: relative;
       }
 
-      /* Included for options UI. TODO(stevenjb): Remove. */
-      [hidden] {
-        display: none !important;
-      }
-
       #icon {
         height: 20px;
         opacity: .65;  /* Equivalent to #5a5a5a */