Android: Keyboard doesn't hide from done button

QLineEdit commits and hides QInputMethod on enter key press. When
Qt::ImhMultiLine input method hint is set, virtual keyboard is not
hidden.

Task-number: QTBUG-37850
Change-Id: I018351caa18bd2116665771e5f024a57182a01b9
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@theqtcompany.com>

src/widgets/widgets/qwidgetlinecontrol.cpp

@@ -1607,6 +1607,13 @@ void QWidgetLineControl::processKeyEvent(QKeyEvent* event)
 
     if (event->key() == Qt::Key_Enter || event->key() == Qt::Key_Return) {
         if (hasAcceptableInput() || fixup()) {
+
+            QInputMethod *inputMethod = QApplication::inputMethod();
+            inputMethod->commit();
+            QWidget *lineEdit = qobject_cast<QWidget *>(parent());
+            if (!(lineEdit && lineEdit->inputMethodHints() & Qt::ImhMultiLine))
+                inputMethod->hide();
+
             emit accepted();
             emit editingFinished();
         }

tests/auto/shared/platforminputcontext.h

@@ -56,6 +56,8 @@ public:
     virtual void reset() { m_resetCallCount++; }
     virtual void commit() {
         m_commitCallCount++;
+        if (m_commitString.isEmpty())
+            return;
         QInputMethodEvent commitEvent;
         commitEvent.setCommitString(m_commitString);
         if (qGuiApp->focusObject())