Move docker push to after success to push only when all tests pass (#1751)

.travis.yml

@@ -55,12 +55,14 @@ before_script:
 
 script:
   - 'if [ ${BUILD_SUITE} = "cluster-test" ]; then
-      ./node_modules/.bin/gulp ci --heapsterServerHost "http://localhost:8082";
+      ./node_modules/.bin/gulp check:local-cluster --heapsterServerHost "http://localhost:8082";
     else
       ./node_modules/.bin/gulp check:code-quality;
     fi'
 
-after_script:
-  - 'if [ ${BUILD_SUITE} = "code-test" ]; then
+after_success:
+  - 'if [ ${BUILD_SUITE} = "cluster-test" ]; then
+      ./node_modules/.bin/gulp ci-push-to-docker:head:cross;
+    else
       ./node_modules/.bin/gulp coverage-codecov-upload;
     fi'

build/ci.js

@@ -19,11 +19,11 @@ import childProcess from 'child_process';
 import gulp from 'gulp';
 
 /**
- * Entry point task for CI environments.
+ * Entry point for CI to push head images to Docker Hub when master builds successfully.
  */
-gulp.task('ci', ['check:local-cluster'], (doneFn) => {
+gulp.task('ci-push-to-docker:head:cross', function(doneFn) {
   if (process.env.TRAVIS) {
-    // Pushe head images when docker user and password are available.
+    // Pushes head images when docker user and password are available.
     if (process.env.TRAVIS_PULL_REQUEST === 'false' && process.env.DOCKER_USER &&
         process.env.DOCKER_PASS) {
       childProcess.exec('docker login -u $DOCKER_USER -p $DOCKER_PASS', (err, stdout, stderr) => {