This was a sort of hackish source only used internally during
version solving. But it causes a couple of subtle bugs because it
never gets registered with the SourceRegistry. That in turn makes
toString() fail on any PackageId with that source since it relies
on the Source being registered.
The simplest fix is to just remove the hacked source and have a
null source in PackageId/Ref mean "root" and handle it specially.
Review URL: https://codereview.chromium.org//12047096
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@17646 260f80e4-7a28-3924-810f-c04153c831b5
This is prep work for SDK constraints. It moves the SDK
version-related code out of SdkSource (which will go away at some
point) into its own library.
I also removed the need for the DART_SDK env variable. It will
still be used if set (which the tests need), but if not set, Pub
will locate the SDK.
Clean up a few static warnings.
Review URL: https://codereview.chromium.org//11871028
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@17433 260f80e4-7a28-3924-810f-c04153c831b5
rnystrom@google.com