Android: silence fallthrough warning in QtInputDelegate

In QtInputDelegate.showSoftwareKeyboard() it's explicitly commented
that it's fallthrough case, so we can just silence it as false warning.

Change-Id: I70482bf96d922ccfa4964e2694e1941767bfc20a
Reviewed-by: Petri Virkkunen <petri.virkkunen@qt.io>

src/android/jar/src/org/qtproject/qt/android/QtInputDelegate.java

@@ -115,6 +115,7 @@ class QtInputDelegate implements QtInputConnection.QtInputConnectionListener, Qt
                     return;
                 m_imm.showSoftInput(m_currentEditText, 0, new ResultReceiver(new Handler()) {
                     @Override
+                    @SuppressWarnings("fallthrough")
                     protected void onReceiveResult(int resultCode, Bundle resultData) {
                         switch (resultCode) {
                             case InputMethodManager.RESULT_SHOWN: