Cleanup: Extract icon related methods outside of util.js

ui/webui/resources/webui_resources.grd

Index: ui/webui/resources/webui_resources.grd
diff --git a/ui/webui/resources/webui_resources.grd b/ui/webui/resources/webui_resources.grd
index dfdb0351ad3412e113b46ac562a2bd500f353c96..9db7c3851a0b9e09bc0d88fb37bac66b1dc86109 100644
--- a/ui/webui/resources/webui_resources.grd
+++ b/ui/webui/resources/webui_resources.grd
@@ -301,6 +301,8 @@ without changes to the corresponding grd file. -->
                  file="html/cr/ui/position_util.html" type="chrome_html" />
       <structure name="IDR_WEBUI_HTML_EVENT_TRACKER"
                  file="html/event_tracker.html" type="chrome_html" />
+      <structure name="IDR_WEBUI_HTML_ICON"
+                 file="html/icon.html" type="chrome_html" />
       <structure name="IDR_WEBUI_HTML_I18N_TEMPLATE"
                  file="html/i18n_template.html" type="chrome_html" />
       <structure name="IDR_WEBUI_HTML_LOAD_TIME_DATA"
@@ -429,6 +431,8 @@ without changes to the corresponding grd file. -->
                  file="js/cr/ui/touch_handler.js" type="chrome_html" />
       <structure name="IDR_WEBUI_JS_EVENT_TRACKER"
                  file="js/event_tracker.js" type="chrome_html" />
+      <structure name="IDR_WEBUI_JS_ICON"
+                 file="js/icon.js" type="chrome_html" flattenhtml="true" />
       <structure name="IDR_WEBUI_JS_I18N_TEMPLATE_NO_PROCESS"
                  file="js/i18n_template_no_process.js"
                  type="chrome_html" />