BUG: Fix shadowed variable in TubeGraphKernel

Also make variables const, where appropriate.

Change-Id: I78a5ef4297bc808c2ed99d24353e8676943db2c7
Merge topic 'FixTubeGraphKernelShadowing'

e655143 BUG: Fix shadowed variable in TubeGraphKernel
STYLE: Cleanup code style in Applications

Change-Id: I5a2a312cf65748c759e0ee959dd838fc32f2f1f7