[wasm] Add support for native relinking after Build, and AOT after publish

[radical]

Wasm app build can run in two scenarios:

1. For build, eg. when running the app in VS, or dotnet build foo.csproj
2. For Publish, eg, when publishing the app to a folder, or Azure

A dotnet wasm app has some native wasm files (dotnet.wasm, and dotnet.js). How these files are obtained, or generated:

• Build

  • with no native libraries referenced (AOT setting is ignored here)
    • files from the runtime pack are used as-is
  • with native libraries referenced
    • dotnet.wasm is relinked with the native libraries

• Publish

  • dotnet.wasm is relinked with the native libraries, and updated pinvoke/icalls from the trimmed assemblies
  • if RunAOTCompilation=true, then the relinking includes AOT'ed assemblies

Build

Implementation:

• Target WasmBuildApp

• runs after Build by default

  • which can be disabled by $(DisableAutoWasmBuildApp)
  • or the run-after target can be set via $(WasmBuildAppAfterThisTarget)

• To run a custom target

  • before any of the wasm build targets, use $(WasmBuildAppDependsOn), and prepend your target name to that
  • after any of the wasm build targets, use AfterTargets="WasmBuildApp" on that target

• Avoid depending on this target, because it is available only when the workload is installed. Use $(WasmNativeWorkload) to check if it is installed.

Publish

Implementation:

• This part runs as a nested build using a MSBuild task, which means that the project gets reevaluated. So, if there were any changes made to items/properties in targets before this, then they won't be visible in the nested build.

• By default WasmTriggerPublishApp runs after the Publish target, and that triggers the nested build

  • The nested build runs WasmNestedPublishApp, which causes Build, and Publish targets to be run
  • Because this causes Build to be run again, if you have any targets that get triggered by that, then they will be running twice.
    • But the original build run, and this publish run can be differentiated using $(WasmBuildingForPublish)

• WasmTriggerPublishApp essentially just invokes the nested publish

  • This runs after Publish

    • which can be disabled by $(DisableAutoWasmPublishApp)
    • or the run-after target can be set via $(WasmTriggerPublishAppAfterThisTarget)

  • To influence the wasm build for publish, use WasmNestedPublishApp

    • To run a custom target before it, use $(WasmNestedPublishAppDependsOn)
    • to run a custom target after it, use AfterTargets="WasmNestedPublishApp"

  • If you want to dependsOn on this, then use DependsOnTargets="WasmTriggerPublishApp"

Fixes #56783, and #53612

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[ghost]

Tagging subscribers to 'arch-wasm': @lewing
See info in area-owners.md if you want to be subscribed.

Issue Details

---

!!WIP!!

Based on the incremental build PR

Author:	radical
Assignees:	-
Labels:	arch-wasm
Milestone:	-

[radical]

/azp run runtime,runtime-staging

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[ghost]

Tagging subscribers to this area: @directhex
See info in area-owners.md if you want to be subscribed.

Issue Details

---

!!WIP!!

Based on the incremental build PR

Author:	radical
Assignees:	-
Labels:	arch-wasm, area-Infrastructure-mono
Milestone:	-

[radical]

1 failing test on wasm/windows is #58812

[steveisok]

LGTM!

[radical]

/backport to release/6.0

[github-actions]

Started backporting to release/6.0: https://github.com/dotnet/runtime/actions/runs/1219117683

[github-actions]

@radical backporting to release/6.0 failed, the patch most likely resulted in conflicts:

$ git am --3way --ignore-whitespace --keep-non-patch changes.patch

Applying: rebased
Applying: disable non-wasm builds
Applying: Fix helix work item name
Applying: fix test
Applying: get all the assemblies from the publishdir
Applying: AOTCompiler: Expand the paths used with MONO_PATH
Applying: Implement support for skipping assemblies for AOT
Applying: Update blazorwasm targets file with a locally patched copy
Applying: Cleanup
Applying: fix path for copying blazorwasm targets file
Applying: Fix tests on emsdk
Applying: Don't fixup runtime pack paths when not using workloads
Applying: update platform-matrix
error: sha1 information is lacking or useless (eng/pipelines/common/platform-matrix.yml).
error: could not build fake ancestor
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0013 update platform-matrix
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".
Error: The process '/usr/bin/git' failed with exit code 128

Please backport manually!

[radical]

Marking this as dont-merge for now, in favor of #58913 which combines this, and #58306 .

[radical]

Merged in #58913 .