UI Picker dialog doesn't stop loading repo= URL

[ewpatton]

Describe the bug

When the UI picker is presented to users on first run and there is a repo= query parameter, the presentation of the dialog does not pause the startup sequence, causing the project to be loaded and shown behind the picker dialog.

Affects

• Designer
• Blocks editor
• Projects Explorer
• Companion
• Compiled apps
• Buildserver
• Debugging
• Other... (please describe)

Expected behavior

No additional work should be done until the selection is made.

Steps to reproduce

1. Build a fresh copy of master
2. Copy one of our existing tutorial URLs from the website and substitute localhost:8888 for ai2.appinventor.mit.edu
3. Go through the login, TOS pages to get to the UI picker dialog. Note the project loading in the background

Note that this may also affect loading from the gallery but I did not test that.

[cindyloo]

I opened up
https://ai2.appinventor.mit.edu/?locale=en&repo=http%3A%2F%2Fappinventor.mit.edu%2Fyrtoolkit%2FAI%2FaiaFiles%2FimageClassification%2FWhatIsIt.asc in incognito mode. I went through the login, but am unclear as to why it would be a bad thing for the repo to load. I did not see the picker dialog..

[cindyloo]

it must be a new user so that ShowUIPicker is True in UserSettings

    return userSettings.getSettings(SettingsConstants.USER_GENERAL_SETTINGS)
            .getPropertyValue(SettingsConstants.SHOW_UIPICKER).equalsIgnoreCase("True");
  }```

called in `handleQueryString()`