Chrome OS: 10452.74.0, 66.0.3359.137 beta channel eve, elm, caroline devices

What steps will reproduce the problem?
1. Open Files app
2. Perform copy operation (single or multiple or a folder) from Gdrive to Downloads/USB folder.

What is the expected result?
Files should be successfully copied.

What happens instead?
Sometimes copy operation operation is successful. Sometimes only few files or a part of the file is copied successfully.
Observed error message 'Copy operation failed....'

Also copy operation was very slow.

Filed feedback report:
https://feedback.corp.google.com/product/208/neutron?lView=rd&lRSort=1&lROrder=2&lRFilter=1&lReportSearch=copy&lReport=85361275973

Attached screenshots.
 

Deleted: Screenshot 2018-04-25 at 12.18.16 PM.png 146 KB

	Screenshot 2018-04-25 at 12.18.16 PM.png 146 KB View Download

Deleted: Screenshot 2018-04-25 at 12.15.54.png 590 KB

	Screenshot 2018-04-25 at 12.15.54.png 590 KB View Download