Merge branch 'shared-brotli' of https://github.com/google/brotli into shared-brotli

# Conflicts:
#	c/enc/backward_references.c
#	c/enc/encoder_dict.c
#	c/enc/encoder_dict.h
#	docs/decode.h.3
#	java/org/brotli/wrapper/enc/Encoder.java
#	java/org/brotli/wrapper/enc/EncoderJNI.java
#	java/org/brotli/wrapper/enc/UseCompoundDictionaryTest.java