GitLab

* src/image.c (image_get_dimension, lookup_image): Handle `ch'
and `cw' dimension specifiers in addition to `em'.
* src/dispextern.h: Add new members `face_font_height' and
`face_font_width' to `struct image'.

* doc/lispref/display.texi (Image Descriptors): Document
`ch' and `cw'.