fix(debugger): console.dir not displayed correctly in Safari inspector

[mbektchiev]

Note Merged to release as well (with #935)

consoleAgent prints them correctly only when they're constructed
using the overload accepting ScriptArguments.

Regression has been introduced with #912

PR Checklist

• The PR title follows our guidelines: https://github.com/NativeScript/NativeScript/blob/master/CONTRIBUTING.md#commit-messages.
• There is an issue for the bug/feature this PR is for. To avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it.
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• Tests for the changes are included.

What is the current behavior?

When console.dir({a:1}) is executed by the application or in the console window of Safari Inspector the output contains only undefined.

What is the new behavior?

console.dir correctly displays the object in the console window.

Fixes #930