In the Review Request screen, failing to connect to the web server while

uploading a file using the Update -> Add File dialog would result in a

JavaScript error.
The server response message is parsed as a JSON object. If the server does

not have a response message, which is the case when the connection to the

web server fails, the JSON object parsed from the response message would be

null, resulting in an error when trying to access members of the object

later.
Null checks were added prior to accessing members of the JSON object. This

prevents the JavaScript from simply crashing. A default error message was

added, reading "Unknown Error" if the JSON object is null.
With the fix in place, failing to connect to the web server during a file

upload in the Review Request screen displays "Unknown Error", without any

JavaScript errors.

Ran JSTests.
Tested manually by attempting to upload a file while the server was off.

There were no JavaScript errors, and the displayed error message read

"Unknown Error".