[MD settings] .settings-row.wide and reduce use of flex layout

chrome/browser/resources/settings/appearance_page/appearance_page.html

Index: chrome/browser/resources/settings/appearance_page/appearance_page.html
diff --git a/chrome/browser/resources/settings/appearance_page/appearance_page.html b/chrome/browser/resources/settings/appearance_page/appearance_page.html
index fcc30552e0f7c06a18b6a4641c156b9c1bab9162..c8b921b5682161a7a1065a235779cfb8706d0baa 100644
--- a/chrome/browser/resources/settings/appearance_page/appearance_page.html
+++ b/chrome/browser/resources/settings/appearance_page/appearance_page.html
@@ -1,7 +1,7 @@
+<link rel="import" href="chrome://resources/html/polymer.html">
+
 <link rel="import" href="chrome://resources/html/i18n_behavior.html">
 <link rel="import" href="chrome://resources/html/md_select_css.html">
-<link rel="import" href="chrome://resources/html/polymer.html">
-<link rel="import" href="chrome://resources/polymer/v1_0/iron-flex-layout/iron-flex-layout-classes.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/neon-animation/neon-animatable.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-button/paper-button.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button-light.html">
@@ -83,7 +83,7 @@
           </template>
 </if>
 <if expr="is_linux and not chromeos">
-          <div class="layout horizontal center" hidden="[[!showThemesSecondary_(
+          <div class="settings-row" hidden="[[!showThemesSecondary_(
               prefs.extensions.theme.id.value, useSystemTheme_)]]"
               id="themesSecondaryActions">
             <div class="separator"></div>