Don't mark YAML editor as immediately changed

[spadgett]

This fixes two issues:

• Don't enable the save button before the user modifies the YAML. The intent in the code is for the button to only enable after the user types something.
• Don't prompt about unsaved changes when the user navigates away immediately.

[jwforres]

is this always going to work or are we creating a race condition where it will just work most of the time

[spadgett]

I can't find a cleaner way. It always works in my testing.

We could do something like this:

    // onChange is called once when the initial content is loaded in the editor.
    var initialized = false;
    $scope.onChange = function() {
      if (initialized) {
        $scope.modified = true;
      }

      initialized = true;
    };

I worry that this will break if they ever change the behavior so that initialization doesn't trigger onChange, however.

Open to alternatives. The worst that happens is that the editor is incorrectly marked dirty so you're prompted when pressing the back button.

[jwforres]

[merge]

[openshift-bot]

Evaluated for origin web console merge up to d39d160

[openshift-bot]

Origin Web Console Merge Results: SUCCESS (https://ci.openshift.redhat.com/jenkins/job/test_pull_requests_origin_web_console/1487/) (Base Commit: 7a49dad)