ci: Update arch image and script.

Don't need a patch for OpenXR-SDK any more.
Include gtk3 in the image for opencv_highgui.
Include ffmpeg.

.gitlab-ci.yml

@@ -7,8 +7,8 @@ variables:
   DEBIAN_DEBS: 'build-essential git cmake meson ninja-build doxygen graphviz libeigen3-dev curl patch python3 pkg-config libx11-dev libxxf86vm-dev libxrandr-dev libxcb-randr0-dev libhidapi-dev libwayland-dev libvulkan-dev glslang-dev glslang-tools libglvnd-dev libgl1-mesa-dev ca-certificates libusb-1.0-0-dev libuvc-dev libavcodec-dev libopencv-dev libudev-dev clang-format-7 codespell'
   DEBIAN_EXEC: 'bash .gitlab-ci/build-openxr-openhmd.sh'
   
-  ARCH_TAG: '2019-04-18.0'
-  ARCH_PKGS: 'git gcc cmake meson ninja pkgconfig python3 diffutils patch doxygen graphviz eigen hidapi libxrandr mesa glslang vulkan-headers vulkan-icd-loader check glfw-x11 libusb opencv'
+  ARCH_TAG: '2019-06-19.0'
+  ARCH_PKGS: 'git gcc cmake meson ninja pkgconfig python3 diffutils patch doxygen graphviz eigen hidapi libxrandr mesa glslang vulkan-headers vulkan-icd-loader check glfw-x11 libusb opencv gtk3 ffmpeg'
   ARCH_EXEC: 'bash .gitlab-ci/build-openxr-openhmd.sh'
   ARCH_CONTAINER_IMAGE: $CI_REGISTRY_IMAGE/archlinux/rolling:$ARCH_TAG
 

.gitlab-ci/build-openxr-openhmd.sh

 #!/bin/sh
 
-# Install the OpenXR SDK, whatever version, with @haagch's patch so we can
-# actually install it system-wide.
+# Install the OpenXR SDK, whatever version, installed system-wide.
 git clone https://github.com/KhronosGroup/OpenXR-SDK
 pushd OpenXR-SDK
-curl 'https://aur.archlinux.org/cgit/aur.git/plain/support_installing_the_loader.diff?h=openxr-loader-git' | patch -p1
 mkdir build
 pushd build
 cmake -DCMAKE_INSTALL_PREFIX=/usr/local -DCMAKE_INSTALL_LIBDIR=lib -DCMAKE_BUILD_TYPE=Release -DBUILD_TESTS=Off -DPRESENTATION_BACKEND=xlib -DDYNAMIC_LOADER=ON -DOpenGL_GL_PREFERENCE=GLVND -GNinja ..