message: Try to fix travis ci builds.
diff: @@ -23,6 +23,14 @@ sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.8 50
  sudo apt-get install -y qt56base qt56translations qt56tools qt56webengine
  +# Fix errors like:
  +#
  +# CMake Error at /opt/qt56/lib/cmake/Qt5Gui/Qt5GuiConfigExtras.cmake:9 (message):
  +# Failed to find "GL/gl.h" in "/usr/include/libdrm"
  +#
  +# See https://github.com/Studio3T/robomongo/issues/1268
  +sudo apt-get install -y mesa-common-dev libglu1-mesa-dev
  +
  git clone --depth=1 --branch=master git://github.com/haiwen/libsearpc.git deps/libsearpc
  git clone --depth=1 --branch=master git://github.com/haiwen/ccnet.git deps/ccnet
  git clone --depth=1 --branch="$SEAFILE_BRANCH" git://github.com/haiwen/seafile.git deps/seafile
  