Random errounous error highlighting

When debugging an Android application and stopped at a break-point and the file imports from libraries downloaded as gradle dependencies such as:

      import android.support.v4.app.ActivityCompat;
      import android.support.v4.content.ContextCompat;
      import android.support.v7.app.AppCompatActivity;

The project builds, deploys and runs as expected in both production and debug modes but  items from the library will be error highlighted. 

The problem is that after shutting down the app the error highlighting remains and appears in the Problems drop down.  Only the tabs that have the above condition and which have been previously selected will have error highlighting on the tab-name and appear in the Problems drop-down. 

Now select another file that contains similar dependencies but which was not previously looked at it will then also display error highlighting and if you close and reopen Problem drop-down.the new file will appear.

First selecting an item in the project tree that does not contain any of the erroneously marked files then deleting the build directory clears all of the error highlighting on both tabs and in the project tree.  But as soon as you open one of the files the highlighting returns.