Use fetch dep script in jenkins script

scripts/fetch-develop.deps.sh

@@ -17,6 +17,7 @@ function dodep() {
     git clone https://github.com/$org/$repo.git $repo
     pushd $repo
     git checkout $curbranch || git checkout develop
+    npm install
     echo "$repo set to branch "`git rev-parse --abbrev-ref HEAD`
     popd
 }

scripts/jenkins.sh

@@ -8,10 +8,13 @@ nvm use 6
 
 set -x
 
+# check out corresponding branches of dependencies
+`dirname $0`/fetch-develop.deps.sh
+
 npm install
 
 # apparently npm 3.10.3 on node 6.4.0 doesn't upgrade #develop target with npm install unless explicitly asked.
-npm install matrix-react-sdk matrix-js-sdk olm
+npm install olm
 
 # install olm. A naive 'npm i ./olm/olm-*.tgz' fails because it uses the url
 # from our package.json (or even matrix-js-sdk's) in preference.
@@ -23,11 +26,6 @@ npm install matrix-react-sdk matrix-js-sdk olm
 #rm -r node_modules/olm
 #cp -r olm/package node_modules/olm
 
-
-# we may be using dev branches of js-sdk and react-sdk, in which case we need to build them
-(cd node_modules/matrix-js-sdk && npm install)
-(cd node_modules/matrix-react-sdk && npm install)
-
 # run the mocha tests
 npm run test