BUG: Uninitialized value in VTKImageIOStreamTest

fixes: http://open.cdash.org/viewDynamicAnalysisFile.php?id=2989542

Change-Id: Ic28da21d4a22b9c005e0ea29298d7e7adf41d069
ENH: Improve const correctness of QuadrilateralCell.

Change-Id: I8a32304bde60b4dd3414e6ed0b30b29b0fce1543
Merge topic 'streamingbug'

2189769 BUG: Uninitialized value in VTKImageIOStreamTest
Merge topic 'coverity_quad'

6e06dd2 ENH: Improve const correctness of QuadrilateralCell.