Forward focus to the contentItem of editable spinboxes

This fixes the scenario where a SpinBox is shown for the first time
with focus, but its editor (TextInput) doesn't have active focus.

tst_focus' keyNavigation.qml had to be adjusted, as an editable
spinbox will now consume key events.

Task-number: QTBUG-60356
Change-Id: I3af0260a22e9633ab6110d6adab7b39a22b849de
Reviewed-by: J-P Nurmi <jpnurmi@qt.io>

src/quicktemplates2/qquickspinbox.cpp

@@ -719,6 +719,16 @@ void QQuickSpinBox::decrease()
     setValue(d->value - d->effectiveStepSize());
 }
 
+void QQuickSpinBox::focusInEvent(QFocusEvent *event)
+{
+    Q_D(QQuickSpinBox);
+    QQuickControl::focusInEvent(event);
+
+    // When an editable SpinBox gets focus, it must pass on the focus to its editor.
+    if (d->editable && d->contentItem && !d->contentItem->hasActiveFocus())
+        d->contentItem->forceActiveFocus(event->reason());
+}
+
 void QQuickSpinBox::hoverEnterEvent(QHoverEvent *event)
 {
     Q_D(QQuickSpinBox);

src/quicktemplates2/qquickspinbox_p.h

@@ -127,6 +127,7 @@ Q_SIGNALS:
     Q_REVISION(2) void inputMethodComposingChanged();
 
 protected:
+    void focusInEvent(QFocusEvent *event) override;
     void hoverEnterEvent(QHoverEvent *event) override;
     void hoverMoveEvent(QHoverEvent *event) override;
     void hoverLeaveEvent(QHoverEvent *event) override;

tests/auto/controls/data/tst_spinbox.qml

@@ -51,6 +51,7 @@
 import QtQuick 2.2
 import QtTest 1.0
 import QtQuick.Controls 2.2
+import QtQuick.Window 2.3
 
 TestCase {
     id: testCase
@@ -422,6 +423,16 @@ TestCase {
         compare(control.value, 100)
     }
 
+    function test_initialFocus() {
+        var window = testCase.Window.window
+        verify(window)
+        compare(window.activeFocusItem, window.contentItem)
+
+        var control = createTemporaryObject(spinBox, testCase, { editable: true, focus: true })
+        verify(control)
+        tryCompare(control.contentItem, "activeFocus", true)
+    }
+
     function test_editable() {
         var control = createTemporaryObject(spinBox, testCase)
         verify(control)

tests/auto/focus/data/keyNavigation.qml

@@ -191,7 +191,6 @@ Item {
         SpinBox {
             id: spinbox
             objectName: "spinbox"
-            editable: true
             value: 50
             KeyNavigation.left: radiobutton2
             KeyNavigation.right: swtich