Unable to save Existing Lightning Components after Summer19 release sandboxes

I also experienced this same issue in one my of custom lightning component. Where it was throwing the error message - There is no such column "ContactId" on User entity;

After struggling the whole day I got a solution for this.

It is just to recompile APEX Classes.

Steps to fix it:

1. Login to Salesforce org
2. Go to setup.
3. Enter "Apex Classes" in the quick search. And then click "Apex Classes".
4. You will see "Compile all classes" link there, just go and press it.
5. Once it completes, go to the component and make the changes and save it. Now it should not show any error.