This library no longer builds on Go versions prior to Go 1.17,
so no longer needs to support compilation specific to AppEngine
environments on Go versions prior to Go 1.11

Related to #615

Change-Id: Ia9579ea2091cb86ee96065affb920370c4ba33ea
Reviewed-on: https://go-review.googlesource.com/c/oauth2/+/570595
Reviewed-by: Matt Hickford <matt.hickford@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cody Oss <codyoss@google.com>
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This is a fix on the googleapis/google-cloud-go#9508.
The aws provider in that library is a ported dependency from here.

Change-Id: I28e1efa4fdb8292210b695a164a55060c83dae88
GitHub-Last-Rev: c425f2d
GitHub-Pull-Request: #711
Reviewed-on: https://go-review.googlesource.com/c/oauth2/+/570875
Reviewed-by: Cody Oss <codyoss@google.com>
Reviewed-by: Chris Smith <chrisdsmith@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

The sts response contains an optional field of `expires_in` and the value can be any integer.

https://github.com/golang/oauth2/blob/master/google/internal/externalaccount/basecredentials.go#L246-L248

In the case of less than `0`, we are going to throw an error. But in the case of equals to `0` practically it means "never expire" instead of "instantly expire" which doesn't make sense.

So we need to not set the expiration value for Token object. The current else if greater or equal is wrong.

It's never triggered only because we are sending positive `3600` in sts response.

Change-Id: Id227ca71130855235572b65ab178681e80d0da3a
GitHub-Last-Rev: a95c923
GitHub-Pull-Request: #687
Reviewed-on: https://go-review.googlesource.com/c/oauth2/+/545895
Reviewed-by: Shin Fan <shinfan@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Cody Oss <codyoss@google.com>
Reviewed-by: Cody Oss <codyoss@google.com>

* move MDS universe retrieval within Compute credentials

Change-Id: I847d2075ca11bde998a06220307626e902230c23
Reviewed-on: https://go-review.googlesource.com/c/oauth2/+/575936
Reviewed-by: Cody Oss <codyoss@google.com>
Auto-Submit: Cody Oss <codyoss@google.com>
Run-TryBot: Cody Oss <codyoss@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>