Attempt to fix Travis per microsoft/vscode#33998

DustinCampbell · DustinCampbell · commit 7f9b5907fbee · 2017-09-15T16:10:35.000-07:00
diff --git a/.travis.yml b/.travis.yml
@@ -16,6 +16,7 @@ addons:
       - ubuntu-toolchain-r-test
     packages:
       - g++-4.9
+      - libsecret-1-dev
 
 install:
 - npm install
