Figure out if using URLFetch if running on AppEngine is necessary

If we can always use NetHttpTransport, we can remove the logic in DefaultHttpTransportFactory.create (in ServiceOptions) to check if we're running on App Engine.

I think it should be safe to remove it.

I run a quick storage example and requests seem to work fine in AppEngine with NetHttpTransport. However from here I read:

com.google.api.client.javanet.NetHttpTransport is discouraged due to a bug in the App Engine SDK itself in how it parses HTTP headers in the response

Is this a known problem in AE? Or has it been already fixed?

Is this a known problem in AE? Or has it been already fixed?

Yes, we saw that before (and we should have mentioned that in the issue).
This was actually the reason we didn't do anything about it yet.
I am %99.9 confident that this should be fine however I could not trace the source of this comment or anyone that knows more about it. We did test it and it seems to be working fine.

This has become irrelevant with recent developments. We are not going to ensure google-cloud-java is compatible with Java 7 on App Engine; Java 8 on App Engine doesn't have the same restrictions with network fetching. Java 8 support on App Engine is quite close, and is being tracked in #1918 . Closing out this issue.