add needed patch for cairo-compmgr to build

pkgbuild/cairo-compmgr-git/PKGBUILD

@@ -17,21 +17,31 @@ depends=("gtk2>=2.16.0" "vala>=0.22" libsm libgl)
 options=(!makeflags
          !libtool)
 
-source=('cairocompmgr::git+https://github.com/gandalfn/Cairo-Composite-Manager.git')
-md5sums=('SKIP')
+source=('cairocompmgr::git+https://github.com/gandalfn/Cairo-Composite-Manager.git'
+        'https://github.com/gandalfn/Cairo-Composite-Manager/pull/4.diff'
+)
+md5sums=('SKIP'
+         '011074cd9687475ebf9ac93fc1f535aa')
 
 pkgver() {
   cd "$srcdir"/cairocompmgr
   git describe --tags | sed 's|-|.|g'
 }
 
-build() {
+prepare() {
   cd "$srcdir"/cairocompmgr
 
   #patch for compatibility with vala 0.22
   sed -i 's!libvala-0.18!libvala-0.22!' configure.ac
   sed -i 's!libvala-0.18!libvala-0.22!' vapi/cairo-compmgr.deps
 
+  #patch needed to build with newer deps version
+  patch -p1 < ../4.diff
+}
+
+build() {
+  cd "$srcdir"/cairocompmgr
+
   ./autogen.sh --prefix=/usr LIBS="-ldl -lgmodule-2.0 -lm -lz"
 
   make