Avoid use of QKeySequence::isEmpty in checks in command implementations.

isEmpty is the wrong thing to check when setting the default shortcut. In addition,
registering commands should not set their shortcut automatically (that
should be defined solely by the default shortcut and reading the
settings, which is done later).

src/plugins/coreplugin/actionmanager/actionmanager.cpp

@@ -377,8 +377,6 @@ Command *ActionManagerPrivate::registerOverridableAction(QAction *action, const
 #endif
         a->setAction(baseAction);
         m_mainWnd->addAction(baseAction);
-        a->setKeySequence(a->keySequence());
-        a->setDefaultKeySequence(QKeySequence());
     } else  if (checkUnique) {
         qWarning() << "registerOverridableAction: id" << id << "is already registered.";
     }
@@ -417,9 +415,6 @@ Command *ActionManagerPrivate::registerShortcut(QShortcut *shortcut, const Id &i
     else
         sc->setContext(context);
 
-    sc->setKeySequence(shortcut->key());
-    sc->setDefaultKeySequence(QKeySequence());
-
     return sc;
 }