Merge branch 'sg/travis-install-dependencies'

The procedure to install dependencies before testing at Travis CI
is getting revamped for both simplicity and flexibility, taking
advantage of the recent move to the vm-based environment.

* sg/travis-install-dependencies:
  travis-ci: install packages in 'ci/install-dependencies.sh'

.travis.yml

@@ -12,16 +12,6 @@ compiler:
   - clang
   - gcc
 
-addons:
-  apt:
-    sources:
-    - ubuntu-toolchain-r-test
-    packages:
-    - language-pack-is
-    - git-svn
-    - apache2
-    - gcc-8
-
 matrix:
   include:
     - env: jobname=GETTEXT_POISON
@@ -50,22 +40,11 @@ matrix:
     - env: jobname=StaticAnalysis
       os: linux
       compiler:
-      addons:
-        apt:
-          packages:
-          - coccinelle
-      before_install:
       script: ci/run-static-analysis.sh
       after_failure:
     - env: jobname=Documentation
       os: linux
       compiler:
-      addons:
-        apt:
-          packages:
-          - asciidoc
-          - xmlto
-      before_install:
       script: ci/test-documentation.sh
       after_failure:
 

ci/install-dependencies.sh

@@ -10,6 +10,15 @@ LFSWHENCE=https://github.com/github/git-lfs/releases/download/v$LINUX_GIT_LFS_VE
 
 case "$jobname" in
 linux-clang|linux-gcc)
+	sudo apt-add-repository -y "ppa:ubuntu-toolchain-r/test"
+	sudo apt-get -q update
+	sudo apt-get -q -y install language-pack-is git-svn apache2
+	case "$jobname" in
+	linux-gcc)
+		sudo apt-get -q -y install gcc-8
+		;;
+	esac
+
 	mkdir --parents "$P4_PATH"
 	pushd "$P4_PATH"
 		wget --quiet "$P4WHENCE/bin.linux26x86_64/p4d"
@@ -32,11 +41,25 @@ osx-clang|osx-gcc)
 	brew link --force gettext
 	brew install caskroom/cask/perforce
 	;;
+StaticAnalysis)
+	sudo apt-get -q update
+	sudo apt-get -q -y install coccinelle
+	;;
+Documentation)
+	sudo apt-get -q update
+	sudo apt-get -q -y install asciidoc xmlto
+	;;
 esac
 
-echo "$(tput setaf 6)Perforce Server Version$(tput sgr0)"
-p4d -V | grep Rev.
-echo "$(tput setaf 6)Perforce Client Version$(tput sgr0)"
-p4 -V | grep Rev.
-echo "$(tput setaf 6)Git-LFS Version$(tput sgr0)"
-git-lfs version
+if type p4d >/dev/null && type p4 >/dev/null
+then
+	echo "$(tput setaf 6)Perforce Server Version$(tput sgr0)"
+	p4d -V | grep Rev.
+	echo "$(tput setaf 6)Perforce Client Version$(tput sgr0)"
+	p4 -V | grep Rev.
+fi
+if type git-lfs >/dev/null
+then
+	echo "$(tput setaf 6)Git-LFS Version$(tput sgr0)"
+	git-lfs version
+fi