Expose RequestError in GoogleApiException when available

[saguiitay]

This should resolve #480

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[saguiitay]

I signed it!

[peleyal]

I'm just curious to know, does it work for you now? I feel that we are missing the JSON tags for all the fields. So for example, I would expect the following property
https://github.com/google/google-api-dotnet-client/blob/9618f6846b29d4b812ba61362215a2c9d25110a9/Src/GoogleApis.Core/Apis/Requests/SingleError.cs#L27
to have [Newtonsoft.Json.JsonPropertyAttribute("domain")] attribute.

Similar to: https://github.com/google/google-api-dotnet-client/blob/9618f6846b29d4b812ba61362215a2c9d25110a9/Src/GoogleApis.Auth/OAuth2/Responses/TokenResponse.cs

Does that make sense?
Thanks!
Eyal

[saguiitay]

I didn't have to touch the deserialization works, since the Error object was already deserialized and used, even before my change (the message of the exception is computed by calling error.ToString())

I'll remove the extra CTRO, and just pass the Error object via the property - it'll make the code cleaner and simpler.

There appears to be 3 tests that fail, but those are not related to the Exception - they are all in the RequestBuilderTest

[peleyal]

Are you saying that our tests fail head? I'll need to check that out...

Otherwise your change seems ok, just make sure you address my comment and we are ready to go. (check also that you signed the CLA, since this pull request is labeled as cla:no.
What is the email address you used to sign?

Thanks!
Eyal

[saguiitay]

I fixed the comment.

I've also already signed the CLA. My Google Account uses a different email than my GitHub account, which might have caused an issue...

[saguiitay]

I signed it!

[googlebot]

CLAs look good, thanks!