Split the Media settings UI into separate microphone and camera sections.

chrome/browser/resources/options/content_settings.css

Index: chrome/browser/resources/options/content_settings.css
diff --git a/chrome/browser/resources/options/content_settings.css b/chrome/browser/resources/options/content_settings.css
index b6112eb0b0cc429633cbd5dcba1d576b7b5c07c7..36c6393af3d8c36c1f3e28a955bd31de595b17f3 100644
--- a/chrome/browser/resources/options/content_settings.css
+++ b/chrome/browser/resources/options/content_settings.css
@@ -79,21 +79,15 @@ div[role='listitem'][controlled-by] {
   -webkit-margin-start: 2em;
 }
 
-.media-device-control {
-  display: table-row;
-}
-
-.media-device-control > span {
-  display: table-cell;
-  min-width: 145px;
-}
-
-.media-device-control > select {
-  display: table-cell;
+select.media-device-control {
   margin: 5px 0;
   width: 12em;
 }
 
+select.media-device-control:empty {
+  display: none;
+}
+
 .exception-setting.media-audio-setting {
   width: 6em;
 }