Upgrade travis to run on bionic

* The python we were using on trusty was EOL and so breaking in sphinx. Rather
  than continuing on trusty, we upgrade to bionic and deliberately target gcc-5
  and clang-3.8 (the only thing we care about being old/minspec to ensure we
  don't break it).

.travis.yml

@@ -1,6 +1,6 @@
 language: cpp
 sudo: required
-dist: trusty
+dist: bionic
 
 branches:
   only:

util/travis/android_setup.sh

@@ -2,7 +2,7 @@
 set -ev
 
 sudo apt-get -qq update
-sudo apt-get install -y cmake
+sudo apt-get install -y cmake openjdk-8-jdk
 
 export ARCH=`uname -m`
 
@@ -12,7 +12,7 @@ wget http://dl.google.com/android/repository/android-ndk-r14b-linux-${ARCH}.zip
 unzip -u -q android-ndk-r14b-linux-${ARCH}.zip
 unzip -u -q sdk-tools-linux-3859397.zip
 
-export JAVA_HOME="/usr/lib/jvm/java-8-oracle"
+export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64
 export ANDROID_NDK=$TRAVIS_BUILD_DIR/android-ndk-r14b
 export ANDROID_SDK=$TRAVIS_BUILD_DIR
 

util/travis/docs_compile.sh

@@ -1,12 +1,9 @@
 #!/bin/sh
 
-# ignore "error" codes in the env script below
-set +e
-
-. /opt/qt56/bin/qt56-env.sh
-
 set -ev
 
+export QT_SELECT=qt5
+
 mkdir build
 pushd build
 

util/travis/docs_setup.sh

@@ -1,12 +1,7 @@
 #!/bin/sh
 set -ev
 
-sudo add-apt-repository -y 'ppa:ubuntu-toolchain-r/test'
-sudo add-apt-repository -y 'ppa:beineri/opt-qt562-trusty'
-sudo add-apt-repository -y 'deb http://apt.llvm.org/precise/ llvm-toolchain-precise-3.8 main'
-wget -O - http://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
 sudo apt-get update -qq
-sudo apt-get install --allow-unauthenticated -y -qq libx11-dev mesa-common-dev libgl1-mesa-dev qt56base libxcb-keysyms1-dev gdb g++-6 python3-pip
+sudo apt-get install --allow-unauthenticated -y -qq libx11-dev mesa-common-dev libgl1-mesa-dev qtbase5-dev libxcb-keysyms1-dev gdb g++-6 python3-pip
 
-sudo pip3 install --upgrade pip setuptools
 sudo pip3 install Sphinx sphinx-rtd-theme

util/travis/linux_compile.sh

@@ -1,18 +1,18 @@
 #!/bin/sh
 
-# ignore "error" codes in the env script below
-set +e
-
-. /opt/qt56/bin/qt56-env.sh 
-
 set -e
 
-# Switch to the gcc version we want
+# Switch to the gcc/clang version we want
 if [ $CC == "gcc" ]; then
-	export CC=gcc-6;
-	export CXX=g++-6;
+	export CC=gcc-5;
+	export CXX=g++-5;
+else
+	export CC=clang-3.8;
+	export CXX=clang++-3.8;
 fi
 
+export QT_SELECT=qt5
+
 mkdir build
 cd build
 if [[ "$RELEASE_BUILD" == "1" ]]; then

util/travis/linux_setup.sh

@@ -1,12 +1,10 @@
 #!/bin/sh
 set -ev
 
-sudo add-apt-repository -y 'ppa:ubuntu-toolchain-r/test'
-sudo add-apt-repository -y 'ppa:beineri/opt-qt562-trusty'
-sudo add-apt-repository -y 'deb http://apt.llvm.org/precise/ llvm-toolchain-precise-3.8 main'
 wget -O - http://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
+sudo add-apt-repository -y 'deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-3.8 main'
 sudo apt-get update -qq 
-sudo apt-get install --allow-unauthenticated -y -qq libx11-dev mesa-common-dev libgl1-mesa-dev qt56base qt56svg qt56x11extras libxcb-keysyms1-dev gdb clang-format-3.8 g++-6
+sudo apt-get install --allow-unauthenticated -y -qq libx11-dev mesa-common-dev libgl1-mesa-dev qtbase5-dev libqt5svg5-dev libqt5x11extras5-dev libxcb-keysyms1-dev gdb clang-format-3.8 clang++-3.8 g++-5
 
 # check last 100 commits are all correctly sized. First line must be no
 # longer than 72 characters, so it fits in git log and github history