Use runtime property settings instead of environment variables for setting startup hook

[jkotalik]

Epic #8833

The startup hook today is set via environment variable right now (https://github.com/aspnet/AspNetCore/blob/master/src/Servers/IIS/AspNetCoreModuleV2/InProcessRequestHandler/inprocessapplication.cpp#L241). Core-setup will eventually be adding an api to set runtime properties like https://github.com/dotnet/core-setup/pull/5336/files#diff-15fec1485f5f10c590d5b840300283ceR233. We should use these instead.

[analogrelay]

Blocked on dotnet/core-setup#5859

[analogrelay]

This is now available in hostfxr 3.0.0-preview6-27707-04, when that lands in our repo (in the next day or so). Reminder (to myself) to check if it's arrived in the triage tomorrow

〉 dumpbin /exports "C:\Users\anurse\Desktop\hostfxr.dll"
Microsoft (R) COFF/PE Dumper Version 14.21.27619.1
Copyright (C) Microsoft Corporation.  All rights reserved.


Dump of file C:\Users\anurse\Desktop\hostfxr.dll

File Type: DLL

  Section contains the following exports for hostfxr.dll

    00000000 characteristics
    FFFFFFFF time date stamp
        0.00 version
           1 ordinal base
          15 number of functions
          15 number of names

    ordinal hint RVA      name

          1    0 00018F60 hostfxr_close
          2    1 00018FB0 hostfxr_get_available_sdks
          3    2 000192A0 hostfxr_get_native_search_directories
          4    3 00019410 hostfxr_get_runtime_delegate
          5    4 000194D0 hostfxr_get_runtime_properties
          6    5 00019600 hostfxr_get_runtime_property_value
          7    6 00019780 hostfxr_initialize_for_app
          8    7 00019900 hostfxr_initialize_for_runtime_config
          9    8 000199F0 hostfxr_main
         10    9 00019B00 hostfxr_main_startupinfo
         11    A 00019BF0 hostfxr_resolve_sdk
         12    B 00019E80 hostfxr_resolve_sdk2
         13    C 0001A130 hostfxr_run_app
         14    D 0001A180 hostfxr_set_error_writer
         15    E 0001A190 hostfxr_set_runtime_property_value <--- !!

[analogrelay]

Looks like it's in our repo now:

〉 dumpbin /exports C:\Code\aspnet\AspNetCore\.dotnet\x64\host\fxr\3.0.0-preview6-27706-03\hostfxr.dll
Microsoft (R) COFF/PE Dumper Version 14.21.27619.1
Copyright (C) Microsoft Corporation.  All rights reserved.


Dump of file C:\Code\aspnet\AspNetCore\.dotnet\x64\host\fxr\3.0.0-preview6-27706-03\hostfxr.dll

File Type: DLL

  Section contains the following exports for hostfxr.dll

    00000000 characteristics
    FFFFFFFF time date stamp
        0.00 version
           1 ordinal base
          15 number of functions
          15 number of names

    ordinal hint RVA      name

          1    0 00018890 hostfxr_close
          2    1 000188E0 hostfxr_get_available_sdks
          3    2 00018BD0 hostfxr_get_native_search_directories
          4    3 00018D40 hostfxr_get_runtime_delegate
          5    4 00018E00 hostfxr_get_runtime_properties
          6    5 00018F30 hostfxr_get_runtime_property_value
          7    6 000190B0 hostfxr_initialize_for_app
          8    7 00019230 hostfxr_initialize_for_runtime_config
          9    8 00019320 hostfxr_main
         10    9 00019430 hostfxr_main_startupinfo
         11    A 00019520 hostfxr_resolve_sdk
         12    B 000197B0 hostfxr_resolve_sdk2
         13    C 00019A60 hostfxr_run_app
         14    D 00019AB0 hostfxr_set_error_writer
         15    E 00019AC0 hostfxr_set_runtime_property_value

  Summary

        4000 .data
        6000 .pdata
       25000 .rdata
        1000 .reloc
        1000 .rsrc
       5F000 .text

[jkotalik]

This change will actually be a lot larger than I expected. It requires a whole new set of hostfxr apis to be used, and may expand into more issues. Defensively putting cost M on it.

[analogrelay]

Blocked on https://github.com/dotnet/core-setup/issues/6388 now.

[jkotalik]

Acceptance checklist (check one item)

• We decided not to take this fix.
• The fix is tests-only.
• The fix contains product changes (check all items below).
  • Relevant XML documentation comments for new public APIs are present.
  • Narrative docs (docs.microsoft.com) are updated. (check one item below)
    • The change requires a new article. An issue with an outline has been filed here: [ISSUE LINK]
    • The change requires a change to an existing article. A docs PR with these changes is linked here: [PR LINK]
    • The change requires no docs changes.
  • Verification has been completed. (check one item below)
    • Verified against ASP.NET Core App Version 3.0.0-preview7.19351.2