trivial: Use the correct branch when building a flatpak bundle

contrib/ci/flatpak.sh

@@ -2,13 +2,37 @@
 set -e
 set -x
 
+# get the correct branch to use
+if [ -z "$FWUPD_BRANCH" ]; then
+    if [ -n $TRAVIS_BRANCH ]; then
+        export FWUPD_BRANCH=$TRAVIS_BRANCH
+    fi
+    if [ -n $TRAVIS_PULL_REQUEST_BRANCH ]; then
+        export FWUPD_BRANCH=$TRAVIS_PULL_REQUEST_BRANCH
+    fi
+fi
+if [ -z "$FWUPD_BRANCH" ]; then
+    GIT_BRANCH=`git rev-parse --abbrev-ref HEAD`
+    if [ $GIT_BRANCH != "HEAD" ]; then
+        export FWUPD_BRANCH=$GIT_BRANCH
+    fi
+fi
+if [ -z "$FWUPD_BRANCH" ]; then
+    exit 0
+fi
+
 # install the runtimes
 flatpak remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo
 flatpak install flathub runtime/org.gnome.Sdk/x86_64/3.28
 flatpak install flathub runtime/org.gnome.Platform/x86_64/3.28
 
-# build the bundle
-flatpak-builder --repo=repo --force-clean --disable-rofiles-fuse build-dir contrib/org.freedesktop.fwupd.json
+# copy in the branch
+rm -rf build
+mkdir build
+envsubst < contrib/org.freedesktop.fwupd.json > build/org.freedesktop.fwupd.json
+
+# build the repo
+flatpak-builder --repo=repo --force-clean --disable-rofiles-fuse build-dir build/org.freedesktop.fwupd.json
 
 # show the files that were included
 tree build-dir

contrib/org.freedesktop.fwupd.json

@@ -167,7 +167,7 @@
                 {
                     "type": "git",
                     "url": "https://github.com/hughsie/fwupd.git",
-                    "branch": "master"
+                    "branch": "$FWUPD_BRANCH"
                 }
             ]
         }