Use chrome_html structure for shared_resources and options2 page.

chrome/browser/resources/options2/browser_options.css

Index: chrome/browser/resources/options2/browser_options.css
diff --git a/chrome/browser/resources/options2/browser_options.css b/chrome/browser/resources/options2/browser_options.css
index fb25415a56ad65e005c9c54b10fe4b59f8adc75b..36c32e70c0c1a0b3924b372b0a8699d0dd44a1d6 100644
--- a/chrome/browser/resources/options2/browser_options.css
+++ b/chrome/browser/resources/options2/browser_options.css
@@ -185,18 +185,22 @@ list:not([disabled]) > .network-group[selected] {
 
 .network-wifi {
   background-image: url('chrome://theme/IDR_STATUSBAR_NETWORK_ARCS_DARK');
+  background-size: 25px;
 }
 
 .network-wimax {
   background-image: url('chrome://theme/IDR_STATUSBAR_NETWORK_BARS_DARK');
+  background-size: 25px;
 }
 
 .network-cellular {
   background-image: url('chrome://theme/IDR_STATUSBAR_NETWORK_BARS_DARK');
+  background-size: 25px;
 }
 
 .network-vpn {
   background-image: url('chrome://theme/IDR_STATUSBAR_VPN');
+  background-size: 25px;
 }
 
 .network-add-connection,
@@ -208,6 +212,7 @@ list:not([disabled]) > .network-group[selected] {
 
 .network-add-connection {
   background-image: url('chrome://theme/IDR_SIDETABS_NEW_TAB');
+  background-size: 16px;
 }
 
 .network-control-inactive {
@@ -216,6 +221,7 @@ list:not([disabled]) > .network-group[selected] {
 
 .network-control-active {
   background-image: url('chrome://theme/IDR_PROFILE_SELECTED');
+  background-size: 16px;
 }
 
 .network-options-button {
@@ -231,6 +237,7 @@ list:not([disabled]) > .network-group[selected] {
 
 .network-menu-item:hover .network-options-button {
   background-image: url('chrome://theme/IDR_STATUSBAR_EDIT');
+  background-size: 25px;
 }
 
 .network-group > .controlled-setting-indicator,