fix(core): add rxjs test

Author: JiaLiPassion

Diff for: .travis.yml

@@ -26,6 +26,7 @@ script:
   - node_modules/.bin/gulp lint
   - node_modules/.bin/gulp format:enforce
   - node_modules/.bin/gulp build
+  - node_modules/.bin/gulp filesize
   - scripts/closure/closure_compiler.sh
   - node_modules/.bin/gulp promisetest
   - npm run test:phantomjs-single
@@ -35,4 +36,4 @@ script:
   - node_modules/.bin/karma start karma-build-sauce-selenium3-mocha.conf.js --single-run
   - node_modules/.bin/gulp test/node
   - node simple-server.js 2>&1> server.log&
-  - node ./test/webdriver/test.sauce.js
+  - node ./test/webdriver/test.sauce.js

Diff for: test/common_tests.ts

@@ -21,6 +21,6 @@ import './zone-spec/sync-test.spec';
 import './zone-spec/fake-async-test.spec';
 import './zone-spec/proxy.spec';
 import './zone-spec/task-tracking.spec';
-// import './rxjs/rxjs.spec';
+import './rxjs/rxjs.spec';
 
 Error.stackTraceLimit = Number.POSITIVE_INFINITY;