Created Unassigned: Exception when doing Update Model Twice in a row [1355]

Following-up to https://entityframework.codeplex.com/workitem/1302 - I found there's a bug if you try the following repro steps:

0. Create a DB with X & Y entities and a 1:many relationship between the two
1. Create new C# console app project
2. Add New _Empty_ EDMX to project
3. Right-click->Update Model from DB. Select just the X entity
4. Model comes back fine
5. Without saving the above do Update Model from DB again and this time select the Y entity

Result:

Error 1 Error 168: The provider did not return a ProviderManifest instance. The provider did not return a ProviderManifest instance. C:\work\test\Test130702_Issue1302_02\Test130702_Issue1302_02\Model2.edmx 7 5 Test130702_Issue1302_02

and no new entity

Expected:

A new Y entity with a new 1:* association between the two entities.