Fix for bug #261942 - Dont reposition dropdown when setting combo sizes

[dkamburov]

Closes 261942 - Horizontal scroll appears in IE 11 when grid enters edit mode, there are combo editor providers and user scrolls the grid horizontally

Additional information (check all that apply):

• Bug fix
• New functionality
• Documentation
• Demos
• CI/CD

Checklist:

• All relevant tags have been applied to this PR
• This PR includes unit tests covering all the new code
• This PR includes API docs for newly added methods/properties
• This PR includes general feature table updates in the root README.MD
• This PR contains breaking changes
• This PR includes behavioral changes and the feature specification has been updated with them

[coveralls]

Coverage decreased (-0.001%) to 82.464% when pulling 9e49795 on dkamburov/fix-261942-18-1 into a3c3167 on 18.1.