XTREE enhancement: New flag XTF2_AUTOEXPROW (&h00400000) works analogously XTF2_AUTOEXPCOL to add extra space to each row to fill out the allotted vertical area of the tree. It only applies to trees with fixed height rows (XTF_VARY flag not set). It is normally accompanied by the XTMF_INTHEIGHT flag (in XTR'MISCFLAGS) which has a similar/related purpose. While XTMF_INTHEIGHT by itself (without XTF2_AUTOEXPROW) cause the height of the tree to shrink slightly, so as to avoid having a partially visible row at the bottom, XTF2_AUTOEXPROW causes the row heights to expand slightly, avoiding the partial row at the bottom but also avoiding the need to shrink the tree height.
Note that while XTF2_AUTOEXPCOL may seem to make XTMF_INTHEIGHT superfluous, the requirement of making each row the same height may result in a small pixel remainder after dividing the extra space between the rows. The XTMF_INTHEIGHT flag will then eliminate that by making a small adjustment to the overall height.
