2 errors overlay when task node doesnt exist

[ascobie]

Development Build.

Browse to a completed task where the node has been removed from the pool. Both the "File {filename} doesn't exist", and the "loading" messages show blended into one message.

This happens when you click on the stdout or stderr tabs:

Edit: while there, we should disable the open in default application button. As clicking it generates a console error: "Cannot read property 'lastModified' of undefined"