From Olivier: - Improvement in THStack::Paint in 1d histograms stacks drawing: The   background of each level is erased with the TFrame color and pattern   before drawing it.
From Olivier:
- Improvement in THStack::Paint in 1d histograms stacks drawing: The
  background of each level is erased with the TFrame color and pattern
  before drawing it.


git-svn-id: ecbadac9c76e8cf640a0bca86f6bd796c98521e3@11268 27541ba8-7e3a-0410-8455-c3a389f83636

dawehner/root,dawehner/root,dawehner/root,dawehner/root,dawehner/root,bbannier/ROOT,bbannier/ROOT,dawehner/root,dawehner/root,bbannier/ROOT,bbannier/ROOT,dawehner/root,bbannier/ROOT,bbannier/ROOT,bbannier/ROOT