Add note to delete code once support library is updated.

Review URL: https://codereview.chromium.org/869363002

Cr-Commit-Position: refs/heads/master@{#312981}

chrome/android/java/src/org/chromium/chrome/browser/widget/ChromeSwitchCompat.java

@@ -18,6 +18,8 @@ import android.widget.Switch;
  * TalkBack doesn't recognize the SwitchCompat class, so it reads events with that classname as
  * "Checkbox". This works around the bug by marking accessibility events from SwitchCompat with the
  * Switch class name, which TalkBack recognizes.
+ *
+ * TODO(newt): Delete this class once the support library is fixed. http://b/19110477
  */
 public class ChromeSwitchCompat extends SwitchCompat {