This is used for quality 11, for qualities <= 9 we already
have a simpler hash table.
The static data size is 252 kB, and this removes the
need to initialize a huge hash map at startup, which was
the reason why transforms had to be disabled by default.
In comparison, the static dictionary itself is 120 kB.
This supports every transform, except the kOmitFirstN.
This will enable processing the input in smaller
chunks than the currently default 2MB for the
slow brotli, while still benefiting from the
larger sliding window.
This commit contains a batch of changes that were made to the Brotli
compression algorithm in the last month. Most important changes:
* Format change: don't push distances representing static dictionary words to the distance cache.
* Fix decoder invalid memory access bug caused by building a non-complete Huffman tree.
* Add a mode parameter to the encoder interface.
* Use different hashers for text and font mode.
* Add a heuristics to the hasher for skipping non-compressible data.
* Exhaustive search of static dictionary during backward reference search.
