Step 3: change file extension C++ -> C

This will break the build.
diff --git a/enc/backward_references.cc b/enc/backward_references.c
similarity index 100%
rename from enc/backward_references.cc
rename to enc/backward_references.c
diff --git a/enc/block_splitter.cc b/enc/block_splitter.c
similarity index 100%
rename from enc/block_splitter.cc
rename to enc/block_splitter.c
diff --git a/enc/brotli_bit_stream.cc b/enc/brotli_bit_stream.c
similarity index 100%
rename from enc/brotli_bit_stream.cc
rename to enc/brotli_bit_stream.c
diff --git a/enc/compress_fragment.cc b/enc/compress_fragment.c
similarity index 100%
rename from enc/compress_fragment.cc
rename to enc/compress_fragment.c
diff --git a/enc/compress_fragment_two_pass.cc b/enc/compress_fragment_two_pass.c
similarity index 100%
rename from enc/compress_fragment_two_pass.cc
rename to enc/compress_fragment_two_pass.c
diff --git a/enc/encode.cc b/enc/encode.c
similarity index 100%
rename from enc/encode.cc
rename to enc/encode.c
diff --git a/enc/entropy_encode.cc b/enc/entropy_encode.c
similarity index 100%
rename from enc/entropy_encode.cc
rename to enc/entropy_encode.c
diff --git a/enc/histogram.cc b/enc/histogram.c
similarity index 100%
rename from enc/histogram.cc
rename to enc/histogram.c
diff --git a/enc/literal_cost.cc b/enc/literal_cost.c
similarity index 100%
rename from enc/literal_cost.cc
rename to enc/literal_cost.c
diff --git a/enc/metablock.cc b/enc/metablock.c
similarity index 100%
rename from enc/metablock.cc
rename to enc/metablock.c
diff --git a/enc/static_dict.cc b/enc/static_dict.c
similarity index 100%
rename from enc/static_dict.cc
rename to enc/static_dict.c
diff --git a/enc/utf8_util.cc b/enc/utf8_util.c
similarity index 100%
rename from enc/utf8_util.cc
rename to enc/utf8_util.c