[patch][ccla] Cannot DnD with a 1px move

[Douglas Hays]

When you mousedown to start dragging and move 1px, then Source:onMouseMove is called and startDrag is signaled. However, since the drag has already started, then _markTargetAnchor should have been signaled as well but it isn't until you move another 1px. This can easily be fixed by reordering the onMouseMove code slightly. The resulting problem can be seen by running: ​http://download.dojotoolkit.org/release-1.3.2/dojo-release-1.3.2/dojox/grid/tests/test_grid_column_reorder.html mousedown on Column 3's header and move the mouse just 1px and release the mouse to drop. The drag start icon can be seen, but the drop causes the column to shift to the start of the table since no target anchor was ever selected.

[Douglas Hays]

simple fix to call _markTargetAnchor after startDrag

[Douglas Hays]

(In [21024]) Fixes #10312 !strict. Reorder code to call _marktargetanchor after startdrag without having to wait for further mouse movement. Add automated test to DateGgrid_mouse.html since it was already setup to move columns and was adversely affected by this issue.