Refactor print preview web ui

chrome/browser/resources/print_preview/settings/margin_settings.html

Index: chrome/browser/resources/print_preview/settings/margin_settings.html
diff --git a/chrome/browser/resources/print_preview/margin_settings.html b/chrome/browser/resources/print_preview/settings/margin_settings.html
similarity index 57%
rename from chrome/browser/resources/print_preview/margin_settings.html
rename to chrome/browser/resources/print_preview/settings/margin_settings.html
index 80d98d87081d16f547880a8d2a21843e649b2ca9..b3faaa3e3994e30fc764c6b5c4fda7b3d06f5a10 100644
--- a/chrome/browser/resources/print_preview/margin_settings.html
+++ b/chrome/browser/resources/print_preview/settings/margin_settings.html
@@ -1,7 +1,9 @@
-<div id="margins-option" class="two-column visible">
+<div id="margin-settings" class="two-column visible margin-settings">
   <h1 i18n-content="marginsLabel"></h1>
   <div class="right-column">
-    <select id="margin-list">
+    <select class="margin-settings-select">
+      <!-- The order of these options must match the natural order of their
+      values, which come from print_preview.ticket_items.MarginsType.Value. -->
       <option i18n-content="defaultMargins" value="0" selected></option>
       <option i18n-content="noMargins" value="1"></option>
       <option i18n-content="minimumMargins" value="2"></option>