Fix break caused by AEL behavioral change in v4.10

[dclaux]

Related Issue

Fixes #5100

Description

Works around a behavioral change in AEL introduced in version 4.10 which causes single expressions such as ${age} to be generated as concat and produce strings instead of the actual type of the expression.

Test card

{
    "type": "AdaptiveCard",
    "$data": {
        "title": "Not empty"
    },
    "body": [
        {
            "type": "TextBlock",
            "size": "Medium",
            "weight": "Bolder",
            "text": "Test card"
        },
        {
            "type": "TextBlock",
            "text": "Should be visible only if title isn't empty",
            "wrap": true,
            "$when": "${title != ''}"
        }
    ],
    "$schema": "http://adaptivecards.io/schemas/adaptive-card.json",
    "version": "1.3"
}

Without this fix, the "$when" clause will incorrectly evaluate to the string "true". With the fix, it will correctly evaluate to the boolean value true.

How Verified

Verified manually in adaptivecards-designer-app

Microsoft Reviewers: Open in CodeFlow

[ghost]

Hi @dclaux. Thanks for helping make the AdaptiveCards JS renderer + tooling better. As additional verification, once the JS build succeeds, please go to the test site to test out your website/designer changes.

[Danieladu]

It looks OK. If change back to the original model is more convenient, we will also consider it.