Fix #308 - Add null check for removing item from uninitialized QuadTree

[barbeau]

I was able to repro #308 NPE by trying to remove an item before any item was inserted - I added a test case that repro's this NPE at the beginning of PointQuadTreeTest.testMultiplePoints():

response = mTree.remove(item1);
assertFalse(response);

Adding a null check in PointQuadTree.remove() fixes this.

[xsorifc28]

Awesome, can't wait for the merge.

[barbeau]

@stephenmcd a friendly reminder to PTAL, when you have a moment. I was able to repro the bug within the unit test and then fix to make it pass, so it's a pretty straightforward fix.

[stephenmcd]

Thanks for the reminder! Looks good.

[philipbjorge]

Thanks all

[natansalda]

Is that possible this bug is introduced again? I still have problem with that, please take a look #348 (comment)

[barbeau]

@natansalda At a glance it looks like this is a different issue - I'll reply on your other comment.