MSTest Windows App SDK 1.1 Unit Test regression repro

This project demonstrates the regression in unit test behavior for Windows App SDK 1.1, reported here: microsoft/testfx#1127

To repro the issue:

  • Select Configuration|Platform = Test11|x64
  • Build the project
  • Run the IsPackaged test

Expected Result: test passes

Actual Result: test fails, because VS is using the wrong test launch mode.

Root cause shows that the regression is due to the removal of this project property in Windows App SDK 1.1: true

This was necessary to address another issue, related to C++ library references: http://task.ms/36741036

As a workaround, WindowsAppContainer=true can be explicitly added back to the project, but that reintroduces the break above, not allowing C++ library references.

Visual Studio should consult not just WindowsAppContainer when determining whether a project is Packaged (conflating two concepts, which was safe with UWP), but should also check whether WindowsPackageType != None.