documentation improvements.
* include/freetype/ftoutln.h (FT_Outline_Embolden): Fix typos.
* src/base/ftbitmap.c (FT_Bitmap_Embolden): Add support for bitmap
of pixel_mode FT_PIXEL_MODE_GRAY2 or FT_PIXEL_MODE_GRAY4.
If xstr is larger than 8 and bitmap is of pixel_mode
FT_PIXEL_MODE_MONO, set xstr to 8 instead of returning error.
* include/freetype/ftbitmap.h (FT_Bitmap_Embolden): New declaration.
* include/freetype/ftoutln.h (FT_Outline_Embolden): New declaration.
* src/base/ftbitmap.c (ft_bitmap_assure_buffer): New auxiliary
function.
(FT_Bitmap_Embolden): New function.
* src/base/ftoutln.c (FT_Outline_Embolden): New function.
* src/base/ftsynth.c: Don't include FT_INTERNAL_CALC_H and
FT_TRIGONOMETRY_H but FT_BITMAP_H.
(FT_GlyphSlot_Embolden): Use FT_Outline_Embolden or
FT_Bitmap_Embolden.
* src/base/ftbitmap.c: Don't include FT_FREETYPE_H and FT_IMAGE_H
but FT_BITMAP_H.
(FT_Bitmap_Copy): New function (from ftglyph.c).
* include/freetype/ftbitmap.h (FT_Bitmap_Copy): New public
definition.
* src/base/ftglyph.c: Include FT_BITMAP_H.
(ft_bitmap_copy): Move to ftbitmap.c.
(ft_bitmap_glyph_init): Remove `memory' variable.
Create new bitmap object if FT_GLYPH_OWN_BITMAP isn't set.
(ft_bitmap_glyph_copy): Use FT_Bitmap_Copy.
(ft_bitmap_glyph_done): Use FT_Bitmap_Done.
(ft_outline_glyph_init): Use FT_Outline_Copy.
* src/base/ftoutln.c (FT_Outline_Copy): Handle source == target.
(FT_Outline_Done_Internal): Check for valid `memory' pointer.
(FT_Outline_Translate, FT_Outline_Reverse, FT_Outline_Render,
FT_Outline_Transform): Check for valid `outline' pointer.
* src/base/ftobjs.c (FT_New_GlyphSlot): Prepend glyph slot to
face->glyph, otherwise a new second glyph slot cannot be created.
(FT_Done_GlyphSlot): Fix memory leak.
(FT_Open_Face): Updated -- face->glyph is already managed by
FT_New_GlyphSlot.
* src/type42/t42objs.c (T42_GlyphSlot_Done): Updated.
Wu, Chia-I (吳佳一)