Merge pull request #17022 from KevinRansom/mefexports

Author: vzarytovskii

Directory.Build.props

@@ -35,7 +35,8 @@
          Don't use it explicitly when building with plain .NET (without Proto or Arcade).
      -->
     <OtherFlags Condition="'$(Configuration)' != 'Proto' and '$(TestingLegacyInternalSignature)' != 'true'">$(OtherFlags) --realsig-</OtherFlags>
-    <OtherFlags Condition="'$(Configuration)' != 'Proto' and '$(TestingLegacyInternalSignature)' == 'true'">$(OtherFlags) --realsig+</OtherFlags>
+    <!-- TBD: Fix MEF Export visibility issues in VS -->
+    <OtherFlags Condition="'$(Configuration)' != 'Proto' and '$(TestingLegacyInternalSignature)' == 'true'">$(OtherFlags) --realsig-</OtherFlags>
 
   </PropertyGroup>