Remove warnings when running unit tests

[Prof Garth Wells]

Running the unit tests generates many of the below warnings:

*** Warning: Evaluating an Expression without knowing the right geometric dimension, assuming 3 is correct.

These swamp other output. Code should be updated to eliminate warnings.

[Martin Sandve Alnæs]

I've been curious about how long it would take for anyone to notice... This will happen when calling eval from python on an Expression that doesn't have an element associated, meaning the geometric dimension is undefined. I added the warning because I think guessing on a dimension is a nasty thing to do that can hide user code bugs, and wanted it clearly shown when it happened. That said, I don't care much if we disable the warning now, or maybe make it show only the first time it happens.

[Chris Richardson]

Who is going to do this? Or will it wait for 1.6?

[Prof Garth Wells]

Should be an easy fix (by adding elements to Expressions, at least in most cases) - let's keep in for 1.5.

[Chris Richardson]

@garth-wells @martinal - do either of you want to fix this for 1.6?

[Martin Sandve Alnæs]

Don't have time. It can wait.

[Anders Logg (Chalmers)]

Removing milestone: 1.7 (automated comment)