Update signout icon and more_settings icon on the md shelf

chrome/browser/resources/chromeos/login/header_bar.css

Index: chrome/browser/resources/chromeos/login/header_bar.css
diff --git a/chrome/browser/resources/chromeos/login/header_bar.css b/chrome/browser/resources/chromeos/login/header_bar.css
index 9189e2b335391643d85fb6ca029d219836f56da7..cae70517097828ba2b8ddf0f83409f597f0d1272 100644
--- a/chrome/browser/resources/chromeos/login/header_bar.css
+++ b/chrome/browser/resources/chromeos/login/header_bar.css
@@ -93,7 +93,8 @@ html[dir=rtl] .header-bar-item {
 #login-header-bar #add-user-button-text,
 #login-header-bar #guest-user-button-text,
 #login-header-bar #more-settings-button-text,
-#login-header-bar #cancel-multiple-sign-in-button-text {
+#login-header-bar #cancel-multiple-sign-in-button-text,
+#login-header-bar #sign-out-user-button-text {
   -webkit-padding-start: 28px;
   background-position: left center;
   background-repeat: no-repeat;
@@ -105,7 +106,8 @@ html[dir=rtl] #login-header-bar #restart-button-text,
 html[dir=rtl] #login-header-bar #add-user-button-text,
 html[dir=rtl] #login-header-bar #more-settings-button-text,
 html[dir=rtl] #login-header-bar #guest-user-button-text,
-html[dir=rtl] #login-header-bar #cancel-multiple-sign-in-button-text {
+html[dir=rtl] #login-header-bar #cancel-multiple-sign-in-button-text,
+html[dir=rtl] #login-header-bar #sign-out-user-button-text {
   background-position: right center;
 }
 
@@ -136,7 +138,9 @@ html[dir=rtl] #login-header-bar #cancel-multiple-sign-in-button-text {
 }
 
 #login-header-bar #more-settings-button-text {
-  background-image: url(chrome://theme/IDR_ICON_MORE_VERT_WHITE);
+  background-image: -webkit-image-set(
+      url(images/1x/more-settings.svg) 1x,
+      url(images/2x/more-settings.svg) 2x );
 }
 
 #login-header-bar #guest-user-button-text {
@@ -150,6 +154,12 @@ html[dir=rtl] #login-header-bar #cancel-multiple-sign-in-button-text {
   background-image: url(chrome://theme/IDR_PANEL_CLOSE);
 }
 
+#login-header-bar #sign-out-user-button-text {
+  background-image: -webkit-image-set(
+      url(images/1x/signout.svg) 1x,
+      url(images/2x/signout.svg) 2x );
+}
+
 .button-restricted {
   border: 1px solid transparent;
   color: white !important;