Fix can't delete search input in CardBrowser after an initial search

The DEL KeyEvent was previously declared to act as a keyboard shortcut
to delete the selected notes. After an initial search which registered
a search query entering DEL attempted to delete the current selected
notes which also resulted in another search(same input) being executed.

The fix registers the DEL keys as a delete notes shortcut ONLY if the
search box of the CardBrowser is not currently available(isIconified
returning true).

AnkiDroid/src/main/java/com/ichi2/anki/CardBrowser.kt

@@ -689,9 +689,16 @@ open class CardBrowser :
                 }
             }
             KeyEvent.KEYCODE_FORWARD_DEL, KeyEvent.KEYCODE_DEL -> {
-                Timber.i("Delete pressed - Delete Selected Note")
-                deleteSelectedNotes()
-                return true
+                if (searchView?.isIconified == false) {
+                    Timber.i("Delete pressed - Search active, deleting character")
+                    // the search box is available and could potentially receive input so handle the
+                    // DEL as a simple text deletion and not as a keyboard shortcut
+                    return false
+                } else {
+                    Timber.i("Delete pressed - Delete Selected Note")
+                    deleteSelectedNotes()
+                    return true
+                }
             }
             KeyEvent.KEYCODE_F -> {
                 if (event.isCtrlPressed) {