Improve WAM error messages

[localden]

Right now, when WAM errors out, it throws an error that a developer might not understand the root cause of:

To reproduce this issue, I used WAM to access a resource without configuring the proper redirect URL.

Per @bgavrilMS:

You have to configure logging and set the PII flag to true there. But that's pretty hard to discover.

The error message from WAM actually told me that I was missing an app-specific redirect URL, but that is not clear from the error surface.

[bgavrilMS]

1. If PII flag is not set, let's add a message like To see this message, set the logging PII flag to true. See aka.ms/logging
2. For the redirect URI in particular, produce an error message telling the end user what they need to register.

[gladjohn]

@localden this is what we show in the scenario you mentioned above,

{"WAM Error \n Error Code: 3399614473 \n Error Message: ApiContractViolation \n WAM Error Message: (pii) \n Internal Error Code: 557973642 \n Possible causes: \n- Invalid redirect uri - ensure you have configured the following url in the application registration in Azure Portal: ms-appx-web://microsoft.aad.brokerplugin/507beea4-593d-47ab-91c9-911d3b0734aa \n"}

are you not seeing this?

[gladjohn]

@localden checking on this one

[localden]

@gladjohn I think in my case it was cut-off (see scroll bar). Things like WAM Error Message: (pii) should likely be updated to something more descriptive.

Where in the source code are the documentation strings handled? Happy to create a PR.

[gladjohn]

that is thrown by MSALRuntime. We can discuss on how to best fix this

[gladjohn]

@gladjohn I think in my case it was cut-off (see scroll bar). Things like WAM Error Message: (pii) should likely be updated to something more descriptive.

Where in the source code are the documentation strings handled? Happy to create a PR.

@MSamWils Is this something that you are working on updating? Do you need a tracking item for this?