message: build: update ninja to version 1.8.2.
diff: @@ -6,11 +6,15 @@ set -e
  apt-get update
  export DEBIAN_FRONTEND=noninteractive
  apt-get install -y curl wget software-properties-common make cmake git python python-pip python3 python3-pip \
  - unzip bc libtool ninja-build automake zip time golang gdb strace wireshark tshark tcpdump
  + unzip bc libtool automake zip time golang gdb strace wireshark tshark tcpdump
  # Install cmake 3.12.
  curl -sLO https://cmake.org/files/v3.12/cmake-3.12.3-Linux-x86_64.tar.gz
  echo "0210f500c71af0ee7e8c42da76954298144d5f72f725ea381ae5db7b766b000e cmake-3.12.3-Linux-x86_64.tar.gz" | sha256sum --check
  tar -zxf cmake-3.12.3-Linux-x86_64.tar.gz -C /usr --strip-components=1
  +# Install ninja 1.8.2.
  +curl -sLO https://github.com/ninja-build/ninja/releases/download/v1.8.2/ninja-linux.zip
  +echo "d2fea9ff33b3ef353161ed906f260d565ca55b8ca0568fa07b1d2cab90a84a07 ninja-linux.zip" | sha256sum --check
  +unzip ninja-linux.zip && mv ninja /usr/bin
  # clang 7.
  curl http://apt.llvm.org/llvm-snapshot.gpg.key | apt-key add -
  apt-add-repository "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-7 main"
  