Fix that editor actions were disabled in navigation bar in debug mode

The mode widget needs the editor manager context, not only the debugger
main window.

Task-number: QTCREATORBUG-16543
Change-Id: Ibe92043a374d9fd507e62998f67c0ce897b198e7
Reviewed-by: hjk <hjk@qt.io>

src/plugins/debugger/debuggerplugin.cpp

@@ -1758,7 +1758,7 @@ bool DebuggerPluginPrivate::initialize(const QStringList &arguments,
     m_modeWindow = createModeWindow(Constants::MODE_DEBUG, m_mainWindow);
     m_mode->setWidget(m_modeWindow);
 
-    m_plugin->addAutoReleasedObject(new DebugModeContext(m_mainWindow));
+    m_plugin->addAutoReleasedObject(new DebugModeContext(m_modeWindow));
 
     m_plugin->addObject(m_mode);