LibLocale was split off from LibUnicode a couple years ago to reduce the
number of applications on SerenityOS that depend on CLDR data. Now that
we use ICU, both LibUnicode and LibLocale are actually linking in this
data. And since vcpkg gives us static libraries, both libraries are over
30MB in size.
This patch reverts the separation and merges LibLocale into LibUnicode
again. We now have just one library that includes the ICU data.
Further, this will let LibUnicode share the locale cache that previously
would only exist in LibLocale.
These allow us to binary search the code point compositions based on
the first code point being combined, which makes the search close to
O(log N) instead of O(N).
This will make it easier to support both string types at the same time
while we convert code, and tracking down remaining uses.
One big exception is Value::to_string() in LibJS, where the name is
dictated by the ToString AO.
We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)
Previously the s_decomposition_mappings variable would refer to other
data in s_decomposition_mappings_data. This would cause thousands of
avoidable relocations at load time.
This saves about 128kB RAM for each process which uses LibUnicode.
This fixes `combine_hangul_code_points` which would try to combine
a LVT syllable with a trailing consonant, resulting in a wrong
character.
Also added a test for this specific case.
The mappings are exposed via `Unicode::code_point_decomposition(u32)`
and `Unicode::code_point_decompositions()`, the latter being useful for
reverse searching a code point from its decomposition.
The normalization code does not make use of `Quick_Check` props (https://www.unicode.org/reports/tr44/#Decompositions_and_Normalization),
meaning no quick check optimizations.
