SettingsAccessor: Fall back to shared settings if merge fails

Better than leaving project unconfigured...

Change-Id: I2ee640e7d8320bb75cd0abd99305eb4a3ad5161e
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>

src/plugins/projectexplorer/settingsaccessor.cpp

@@ -722,7 +722,7 @@ QVariantMap SettingsAccessor::restoreSettings() const
             m_project->setProperty(SHARED_SETTINGS, sharedSettings.m_map);
             if (settings.isValid())
                 mergeSharedSettings(&settings.m_map, sharedSettings.m_map);
-            else
+            if (!settings.isValid())
                 settings = sharedSettings;
         }
     }