FLEX-35267 Updated unit test - made it easier to read, and now we're also testing GridColumnHeaderGroup.containsGlobalCoordinates(). For the test to pass I've improved the logic in GridHeaderViewLayout.getHeaderIndexAt() which, in turn, made a few functions redundant in GridColumnHeaderGroup. All tests currently pass.
FLEX-35260 Now the unit test passes, having been updated to check the column header view boundaries. Other changes: -Now we're ignoring the grid header's right padding, because it doesn't make a visual difference (except in the edge case where, together with the left and right padding, the column widths are wider than the grid's width, in which case the grid header expands beyond the grid limits), but we are starting to take into account bottom and top padding. -Renamed some variables and functions for clarity in GridColumnHeaderView and GridDimensions. -Improved error messages in the unit test