Bug 1248408 - Preserve text from previous a11y event if new event does not provide any. r=mfinkle

MozReview-Commit-ID: 3hIquiKLvl7

--HG--
extra : rebase_source : 46db647654a5dcb9d2388e6856c7cb9bef1c25b4

mobile/android/base/java/org/mozilla/gecko/GeckoAccessibility.java

@@ -208,8 +208,8 @@ public class GeckoAccessibility {
                 for (int i = 1; i < textArray.length(); i++) {
                     sb.append(" ").append(textArray.optString(i));
                 }
+                sVirtualCursorNode.setText(sb.toString());
             }
-            sVirtualCursorNode.setText(sb.toString());
             sVirtualCursorNode.setContentDescription(message.optString("description"));
 
             JSONObject bounds = message.optJSONObject("bounds");