BUG: Memory leak detected by valgrind

The class was not deleting the yy_current_buffer.

Change-Id: I2ae4938ade1d84cacb774ab62f74aef03372b446
Merge branch '12994-xmlmultiblockwriter-improvements-rel' into release
Make some color methods consistent.

In order to use functions like SetTableValue(2, "Blue") in a lookup table
  or other SetColors in derived classes in the same manner,
  these methods should be virtual.
This commit just makes the relevant Set methods virtual.
In the case of vtkProperty, the definition of SetColor(double a[3]) has
  been moved into vtkProperty.cxx, the rationale is that, in VTK classes,
  definitions occur in the implementation file not the header file.

Change-Id: I89fee8eb4902e0847114b068374c3bff0bf10b9d
Merge topic 'Virtualize_Color_Methods-rel' into master

293e5386 Make some color methods consistent.
Merge branch 'Virtualize_Color_Methods-rel' into release

Change-Id: I77e1b3b31a1392fb2bb2031f1ec77cbf8234cc9e
Merge branch 'release'

Change-Id: Id16fefd9dc7d363aa785056f8aa6c462e162707b
Merge topic 'VRMLImporter_MemoryLeak' into master

1df268eb BUG: Memory leak detected by valgrind