BFont::Blocks is now implemented in ServerFont, via a call through the
app_server. It uses fontconfig to iterate through a charset of a font
and stores the defined blocks in a bitmap.
A new API was added, BFont::IncludesBlock, that will allow for arbitrary
testing of a given Unicode block. Since nothing is cached, searching
through an entire charset for a series of Unicode blocks can be quite
slow. In a given block there may be only 1 or 2 characters actually
defined so every character within a block needs to be checked until one
is found, which in a degenerate case will mean the entire block is
checked.
Signed-off-by: Axel Dörfler <axeld@pinc-software.de>