message: Remove redundant if checks
  The check method already contains such checks internally. Besides, it
  was weird that only one set of boundary conditions was checked here.
diff: @@ -95,9 +95,8 @@ void GraphWalker::walkGraph()
  mThisTile.connected(true);
  mTileList.push_back(&mThisTile);
  - if (mDepth > 0) { check({mGridPosition, mDepth - 1}, Direction::Up); }
  - if (mDepth < mTileMap.maxDepth()) { check({mGridPosition, mDepth + 1}, Direction::Down); }
  -
  + check({mGridPosition, mDepth - 1}, Direction::Up);
  + check({mGridPosition, mDepth + 1}, Direction::Down);
  check({mGridPosition + DirectionNorth, mDepth}, Direction::North);
  check({mGridPosition + DirectionEast, mDepth}, Direction::East);
  check({mGridPosition + DirectionSouth, mDepth}, Direction::South);
  