fix windows distribtest and add TODOs to remove hacks

test/distrib/csharp/run_distrib_test.bat

@@ -36,7 +36,17 @@ powershell -Command "Add-Type -Assembly 'System.IO.Compression.FileSystem'; [Sys
 update_version.sh auto
 
 set NUGET=C:\nuget\nuget.exe
-%NUGET% restore || goto :error
+
+@rem TODO(jtattermusch): Get rid of this hack. See #8034
+@rem We can't do just "nuget restore" because restoring a .sln solution doesn't work
+@rem with nuget 3.X. On the other hand, we need nuget 2.12+ to be able to restore
+@rem some of the packages (e.g. System.Interactive.Async), but nuget 2.12
+@rem hasn't been officially released.
+@rem Please note that "Restore nuget packages" in VS2013 and VS2015 GUI works as usual.
+
+cd DistribTest || goto :error
+%NUGET% restore -PackagesDirectory ../packages || goto :error
+cd ..
 
 @call build_vs2015.bat DistribTest.sln %MSBUILD_EXTRA_ARGS% || goto :error
 

tools/run_tests/pre_build_csharp.bat

@@ -38,9 +38,10 @@ cd /d %~dp0\..\..
 set NUGET=C:\nuget\nuget.exe
 
 if exist %NUGET% (
+  @rem TODO(jtattermusch): Get rid of this hack. See #8034
   @rem Restore Grpc packages by packages since Nuget client 3.4.4 doesnt support restore
   @rem by solution
-  @rem Moving into each directory to let the restores work with both nuget 3.4 and 2.8
+  @rem Moving into each directory to let the restores work based on per-project packages.config files
   %NUGET% restore vsprojects/grpc_csharp_ext.sln || goto :error
 
   cd src/csharp

tools/run_tests/pre_build_csharp.sh

@@ -37,9 +37,10 @@ root=`pwd`
 
 if [ -x "$(command -v nuget)" ]
 then
+  # TODO(jtattermusch): Get rid of this hack. See #8034
   # Restoring Nuget packages by packages rather than by solution because of
   # inability to restore by solution with Nuget client 3.4.4
-  # Moving into each directory to let the restores work with nuget 3.4 and 2.8
+  # Moving into each directory to let the restores work based on per-project packages.config files
   cd Grpc.Auth
   nuget restore -PackagesDirectory ../packages
   cd ..