Enabling building of libdav1d on Travis CI

.travis.yml

@@ -1,6 +1,18 @@
 language: android
-dist: trusty
+dist: xenial
 before_install:
+  # Installing meson for libdav1d building
+  - sudo apt-get update
+  - sudo apt-get upgrade
+  - sudo apt-get install dpkg
+  - sudo apt-get install python3.5 python3-pip python3-setuptools python3-wheel ninja-build
+  - sudo rm /usr/bin/python3
+  - sudo ln -s /usr/bin/python3.5 /usr/bin/python3
+  - curl http://archive.ubuntu.com/ubuntu/pool/universe/n/nasm/nasm_2.13.02-0.1_amd64.deb --output nasm_2.13.02-0.1_amd64.deb
+  - sudo dpkg -i nasm_2.13.02-0.1_amd64.deb
+  # - curl http://archive.ubuntu.com/ubuntu/pool/universe/n/ninja-build/ninja-build_1.5.1-0.1ubuntu1_amd64.deb --output ninja-build_1.5.1-0.1ubuntu1_amd64.deb
+  # - sudo dpkg -i ninja-build_1.5.1-0.1ubuntu1_amd64.deb
+  - sudo pip3 install meson
   # Installing the ndk and assembling the FFmpeg
   - yes | sdkmanager "ndk-bundle"
   - yes | sdkmanager "patcher;v4"
@@ -10,4 +22,4 @@ before_install:
   # Keeping track of the NDK version that was used
   - cat $ANDROID_NDK_HOME/source.properties
 script:
-  - bash -e ffmpeg-android-maker.sh --enable-libmp3lame --enable-libaom
+  - bash -e ffmpeg-android-maker.sh --enable-libdav1d --enable-libmp3lame --enable-libaom