Fix System.Interactive.Providers

Ix.NET/Source/System.Interactive.Providers/System.Interactive.Providers.csproj

@@ -7,6 +7,10 @@
     <PackageTags>Ix;Interactive;Extensions;Enumerable</PackageTags>
   </PropertyGroup>
 
+  <PropertyGroup Condition="'$(TargetFramework)' == 'netstandard1.0' OR '$(TargetFramework)' == 'netstandard1.4'">
+    <DefineConstants>$(DefineConstants);CRIPPLED_REFLECTION</DefineConstants>
+  </PropertyGroup>
+
   <ItemGroup>
     <EmbeddedResource Include="Properties\System.Interactive.Providers.rd.xml" />
   </ItemGroup>