In quality 1, use static Huffman codes for distance
and command histograms with <= 128 symbols and dynamic
Huffman codes with static code length codes for the other
histograms.
* Remove default constructors.
* Initialize bit_cost in histogram.Clear().
* Check fseek result in FileSize.
* Replace malloc in BrotliFileIn constructor with "new".
* Catch bad_alloc in bro tool.
* Cluster at most 64 histograms at a time in the first
round of clustering.
* Use a faster histogram cost estimation function.
* Don't compute the log2(total) multiple times in the
block splitter.
Remove the hard-coded constants for window size
and meta-block size.
Initialize internal storage for each metablock
separately and reserve only as much as needed
for the actual input.
The new mode can be used by setting the greedy_block_split
field of BrotliParams to true.
This commit moves all the meta-block processing code
into its own library and moves the meta-block encoding
code to brotli_bit_stream.cc from encode.cc
