Fix context of Locator input

- In the main window, the locator input (actually the status bar)
  visually feels like being part of the mode widget, so give
  it its context.
- In extra editor windows, the whole editor window should have
  "editor manager" context, so that is also active for the locator
  input.

Task-number: QTCREATORBUG-20626
Task-number: QTCREATORBUG-20071
Change-Id: Ib68d6a8177446572ea59c3cc057eca0706173e11
Reviewed-by: Xing Xiong
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/help/helpplugin.cpp

@@ -523,7 +523,7 @@ void HelpPluginPrivate::updateSideBarSource(const QUrl &newUrl)
 void HelpPluginPrivate::setupHelpEngineIfNeeded()
 {
     LocalHelpManager::setEngineNeedsUpdate();
-    if (ModeManager::currentMode() == m_mode.id()
+    if (ModeManager::currentModeId() == m_mode.id()
             || LocalHelpManager::contextHelpOption() == HelpManager::ExternalHelpAlways)
         LocalHelpManager::setupGuiHelpEngine();
 }