Hooked up shortcut callback listener

 Bug: 3272241
 When the cancel button was added the call to register a callback
 listener was accidentally removed. Adding it back.

Change-Id: I45fc205873a4c1d3b9f4faa470cecf7cfed661c7
diff --git a/src/com/android/browser/ShortcutActivity.java b/src/com/android/browser/ShortcutActivity.java
index 33e192a..16a4cbe 100644
--- a/src/com/android/browser/ShortcutActivity.java
+++ b/src/com/android/browser/ShortcutActivity.java
@@ -40,6 +40,7 @@
         mBookmarks.setEnableContextMenu(false);
         mBookmarks.setBreadCrumbMaxVisible(2);
         mBookmarks.setBreadCrumbUseBackButton(true);
+        mBookmarks.setCallbackListener(this);
         View cancel = findViewById(R.id.cancel);
         if (cancel != null) {
             cancel.setOnClickListener(this);