/usr/include/ is in libprotoc-dev 2.6.1-1.
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/usr/include/google/
/usr/include/google/protobuf/
/usr/include/google/protobuf/compiler/
/usr/include/google/protobuf/compiler/plugin.pb.h
/usr/include/google/protobuf/compiler/plugin.h
/usr/include/google/protobuf/compiler/parser.h
/usr/include/google/protobuf/compiler/importer.h
/usr/include/google/protobuf/compiler/command_line_interface.h
/usr/include/google/protobuf/compiler/code_generator.h
/usr/include/google/protobuf/compiler/plugin.proto
/usr/include/google/protobuf/compiler/java/
/usr/include/google/protobuf/compiler/java/java_generator.h
/usr/include/google/protobuf/compiler/python/
/usr/include/google/protobuf/compiler/python/python_generator.h
/usr/include/google/protobuf/compiler/cpp/
/usr/include/google/protobuf/compiler/cpp/cpp_generator.h