ProjectExplorer: Set focus to TargetSetupPage when shown

This ensures the "Configure Project" button can be activated
with <Return>

Fixes: QTCREATORBUG-20720
Change-Id: Ib20848cf2b4a1a2fcd33f9652a9a09796fd85c54
(cherry picked from commit b1d3eee42d)
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/projectexplorer/targetsetuppage.cpp

@@ -540,6 +540,12 @@ void TargetSetupPage::doInitializePage()
     updateVisibility();
 }
 
+void TargetSetupPage::showEvent(QShowEvent *event)
+{
+    WizardPage::showEvent(event);
+    setFocus(); // Ensure "Configure Project" gets triggered on <Return>
+}
+
 void TargetSetupPage::changeAllKitsSelections()
 {
     if (m_ui->allKitsCheckBox->checkState() == Qt::PartiallyChecked)

src/plugins/projectexplorer/targetsetuppage.h

@@ -88,6 +88,8 @@ public:
 private:
     void doInitializePage();
 
+    void showEvent(QShowEvent *event) final;
+
     void handleKitAddition(Kit *k);
     void handleKitRemoval(Kit *k);
     void handleKitUpdate(Kit *k);