Make sure to instantiate an Assembly instance for every assembly loaded using
the cached list of assemblies.
Fixes the following test failures:
1. Xamarin.MTouch.RebuildTest_WithExtensions("single","",False,System.String[]) : second build
Expected: 0
But was: 1
2. Xamarin.MTouch.RebuildTest_WithExtensions("dual","armv7,arm64",False,System.String[]) : second build
Expected: 0
But was: 1
3. Xamarin.MTouch.RebuildTest_WithExtensions("llvm","armv7+llvm",False,System.String[]) : second build
Expected: 0
But was: 1
4. Xamarin.MTouch.RebuildTest_WithExtensions("debug","",True,System.String[]) : second build
Expected: 0
But was: 1
5. Xamarin.MTouch.RebuildTest_WithExtensions("single-framework","",False,System.String[]) : second build
Expected: 0
But was: 1