MD-Settings: A11y - Label drop down menus.

chrome/browser/resources/settings/device_page/display.html

Index: chrome/browser/resources/settings/device_page/display.html
diff --git a/chrome/browser/resources/settings/device_page/display.html b/chrome/browser/resources/settings/device_page/display.html
index 3993511a308338a15e2ecfaba50c4f1a7f63b051..35fa02327068d7443c59e765c2aaf4382a4d49a3 100644
--- a/chrome/browser/resources/settings/device_page/display.html
+++ b/chrome/browser/resources/settings/device_page/display.html
@@ -90,9 +90,12 @@
       </div>
       <div class="settings-box embedded"
           hidden$="[[!showDisplaySelectMenu_(displays, selectedDisplay)]]">
-        <div class="start">$i18n{displayScreenTitle}</div>
+        <div id="displayScreenTitle" class="start">
+          $i18n{displayScreenTitle}
+        </div>
         <div class="md-select-wrapper">
           <select class="md-select" on-change="updatePrimaryDisplay_"
+              aria-labelledby="displayScreenTitle"
               value="[[getDisplaySelectMenuIndex_(
                   selectedDisplay, primaryDisplayId)]]">
             <option value="0">$i18n{displayScreenPrimary}</option>
@@ -114,9 +117,12 @@
         </settings-slider>
       </div>
       <div class="settings-box embedded">
-        <div class="start textarea">$i18n{displayOrientation}</div>
+        <div id="displayOrientation" class="start textarea">
+          $i18n{displayOrientation}
+        </div>
         <div class="md-select-wrapper">
           <select class="md-select" value="[[selectedDisplay.rotation]]"
+              aria-labelledby="displayOrientation"
               on-change="onOrientationChange_">
             <option value="0">$i18n{displayOrientationStandard}</option>
             <option value="90">90</option>