project successfully prepare when xml file is broken

[miroslavaivanova]

Environment Provide version numbers for the following components (information can be retrieved by running tns info in your project folder or by inspecting the package.json of the project):

• CLI: 5.4.0

Describe the bug If your xml file is broken and you prepare a project, you will see that it will successfully build.

To Reproduce

1. tns create app
2. change something in main-page.xml, for example remove >
3. tns prepare android/ios
4. project will succesfully build. Missing

..../TestApp/app/main-page.xml has syntax errors.
warning
unclosed xml attribute

Expected behavior should error in console