use trusty, install libxkbcommon-dev from wily

.travis.yml

@@ -1,23 +1,29 @@
+# Use Ubuntu 14.04 (trusty), as per http://blog.travis-ci.com/2015-10-14-opening-up-ubuntu-trusty-beta/
+sudo: required
+dist: trusty
 language: c
 compiler:
   - gcc
-# TODO: re-enable clang once libxkbcommon >= 0.5.0 can be installed from packages. Compiling libxkbcommon with clang fails in the libtool step.
-#  - clang
+  - clang
 addons:
   apt:
-    sources:
-    - llvm-toolchain-precise-3.5
-    # ubuntu-toolchain-r-test contains libstdc++6 >= 4.8 which libllvm3.5 needs.
-    - ubuntu-toolchain-r-test
     packages:
     - clang-format-3.5
-    - libllvm3.5
-install:
-  # TODO: Once libxkbcommon >= 0.5.0 is in Debian, install it from there.
-  # These are the Build-Depends of libxkbcommon:
-  - sudo apt-get install pkg-config xutils-dev bison flex libx11-dev libxcb-xkb-dev x11-xkb-utils x11proto-core-dev x11proto-kb-dev xkb-data xvfb
-  - (cd /tmp && wget -nv https://github.com/xkbcommon/libxkbcommon/archive/xkbcommon-0.5.0.tar.gz && tar xf xkbcommon-0.5.0.tar.gz && cd libxkbcommon-xkbcommon-0.5.0; ./autogen.sh && ./configure && make && sudo make install)
-  - sudo apt-get install pkg-config libpam0g-dev libcairo2-dev libxcb1-dev libxcb-dpms0-dev libxcb-image0-dev libxcb-util0-dev libev-dev libxcb-xinerama0-dev libxcb-xkb-dev libxkbfile-dev
+    - pkg-config
+    - libpam0g-dev
+    - libcairo2-dev
+    - libxcb1-dev
+    - libxcb-dpms0-dev
+    - libxcb-image0-dev
+    - libxcb-util0-dev
+    - libev-dev
+    - libxcb-xinerama0-dev
+    - libxcb-xkb-dev
+before_install:
+  - "echo 'APT::Default-Release \"trusty\";' | sudo tee /etc/apt/apt.conf.d/default-release"
+  - "echo 'deb http://archive.ubuntu.com/ubuntu/ wily main universe' | sudo tee /etc/apt/sources.list.d/wily.list"
+  - sudo apt-get update
+  - sudo apt-get --force-yes -y install -t wily libxkbcommon-dev libxkbcommon-x11-dev
 script:
   - make -j
   - clang-format-3.5 -i *.[ch] && git diff --exit-code || (echo 'Code was not formatted using clang-format!'; false)