fixup! improve comment

Author: Narretz

src/ng/directive/input.js

@@ -1248,9 +1248,11 @@ function baseInputType(scope, element, attr, ctrl, $sniffer, $browser) {
       composing = true;
     });
 
+    // Support: IE9+
     element.on('compositionupdate', function(ev) {
-      // To end composition when ev.data is empty string on 'compositionupdate' event.
-      // When the input has blurred, IE only triggers 'compositionupdate' event instead of 'compositionend'.
+      // End composition when ev.data is empty string on 'compositionupdate' event.
+      // When the input de-focusses (e.g. by clicking away), IE triggers 'compositionupdate'
+      // instead of 'compositionend'.
       if (ev.data === '') composing = false;
     });