Fix packaging

Author: stephentoub

src/libraries/System.Linq.AsyncEnumerable/README.md

@@ -15,4 +15,4 @@ See the [Help Wanted](https://github.com/dotnet/runtime/issues?q=is%3Aissue+is%3
 
 ## Deployment
 
-System.Linq.AsyncEnumerable is a NuGet package that gets shipped with every release of .NET.
+System.Linq.AsyncEnumerable is shipped as part of the .NET shared framework and as a NuGet package.

src/libraries/System.Linq.AsyncEnumerable/src/System.Linq.AsyncEnumerable.csproj

@@ -2,12 +2,13 @@
 
   <PropertyGroup>
     <TargetFrameworks>$(NetCoreAppCurrent);$(NetCoreAppPrevious);$(NetCoreAppMinimum);netstandard2.0;$(NetFrameworkMinimum)</TargetFrameworks>
-    <NoWarn>$(NoWarn);CS1998</NoWarn>
-  </PropertyGroup>
+    <IsPackable>true</IsPackable>
+    <NoWarn>$(NoWarn);CS1998</NoWarn> <!-- Various IAsyncEnumerable implementations that don't need to use await -->
 
-  <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
-  <PropertyGroup>
-    <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
+    <!-- Disabling baseline validation since this is a brand new package.
+         Once this package has shipped a stable version, the following line
+         should be removed in order to re-enable validation. -->
+    <DisablePackageBaselineValidation>true</DisablePackageBaselineValidation>
   </PropertyGroup>
 
   <ItemGroup>

src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/System.Text.Json.SourceGeneration.Tests.targets

@@ -148,6 +148,7 @@
   <ItemGroup Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'">
     <ProjectReference Include="..\..\src\System.Text.Json.csproj" />
     <ProjectReference Include="$(LibrariesProjectRoot)System.Collections.Immutable\src\System.Collections.Immutable.csproj" />
+    <ProjectReference Include="$(LibrariesProjectRoot)System.Linq.AsyncEnumerable\src\System.Linq.AsyncEnumerable.csproj" />
     <Reference Include="System.ComponentModel.DataAnnotations" />
     <PackageReference Include="System.ComponentModel.Annotations" Version="$(SystemComponentModelAnnotationsVersion)"/>
   </ItemGroup>
@@ -165,7 +166,6 @@
   <ItemGroup>
     <DefaultReferenceExclusion Include="System.Text.Json.SourceGeneration" />
     <ProjectReference Include="$(LibrariesProjectRoot)Microsoft.Extensions.Primitives\src\Microsoft.Extensions.Primitives.csproj" />
-    <ProjectReference Include="$(LibrariesProjectRoot)System.Linq.AsyncEnumerable\src\System.Linq.AsyncEnumerable.csproj" />
   </ItemGroup>
 
   <Target Name="FixIncrementalCoreCompileWithAnalyzers" BeforeTargets="CoreCompile">