VcsBase: Fix enabling git actions after rebase

Delay the state changed signal for proper evaluation
(a file check for `rebase-apply` is run when the
signal is emitted)

This fixes that Git "Rebasing" stayed in the title
bar when rebasing was long finished and therefore
the rebase actions stayed disabled.

TODO: The [REBASING] message in the projects view is
not fixed, it disappears when clicking the title bar.

Fixes: QTCREATORBUG-31815
Change-Id: Ic83949dfdaf26df3af8149457e3f282ff1bcefe5
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/vcsbase/vcsbaseplugin.cpp

@@ -30,6 +30,7 @@
 #include <QSharedData>
 #include <QProcessEnvironment>
 #include <QTextCodec>
+#include <QTimer>
 
 using namespace Core;
 using namespace Utils;
@@ -308,8 +309,10 @@ void StateListener::slotStateChanged()
         state.clearPatchFile(); // Need a repository to patch
 
     qCDebug(stateLog).noquote() << "VC:" << (vc ? vc->displayName() : QString("None")) << state;
-    EditorManager::updateWindowTitles();
-    emit stateChanged(state, vc);
+    QTimer::singleShot(500, this, [this, state, vc] {
+        EditorManager::updateWindowTitles();
+        emit stateChanged(state, vc);
+    });
 }
 
 } // namespace Internal