This commit also improves the start values of vertical phantom
points. Kudos to Greg Hitchcock for help.
* src/truetype/ttgload.c (TT_Get_VMetrics): Add parameter to pass
`yMax' value. Replace code with fixed Microsoft definition.
(tt_get_metrics): Updated.
(TT_LOADER_SET_PP): Add explanation how to initialize phantom
points, taken from both the OpenType specification and private
communication with Greg (which will eventually be added to the
standard).
Fix horizontal position of `pp3' and `pp4'.
* src/truetype/ttgload.h: Updated.
* src/truetype/ttdriver.c (tt_get_advances): Updated.
* docs/CHANGES: Updated.
7e4b0fbfdd