feat(remaining-time-display): displays remaining time in x-small or tiny

When the current time and media duration are displayed, it's easy for the user
to visualize the time remaining to play. However, when the player is displayed
in x-small or tiny, no time indication is shown.

- modify `_layout.scss` to display the remaining time when the player is
displayed in x-small or tiny.

scss/components/_layout.scss

@@ -45,6 +45,15 @@
   font-weight: bold;
 }
 
+&:not(.vjs-live) {
+  &.vjs-layout-x-small .vjs-remaining-time,
+  &.vjs-layout-tiny .vjs-remaining-time {
+    display: block;
+    padding: 0;
+    font-weight: bold;
+  }
+}
+
 /*
 ******************************************************************************
 -- Progress control