[browser] throttling

[pavelsavara]

• enable throttling for all file types.
• leaveThrottling(); after instantiation for some of them
• add optional asset.priority for later use
• make sure that onDownloadedAsset(); is counted even when it fails
• fix webcil name

[dotnet-policy-service]

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[Copilot]

Pull request overview

This pull request refactors the download throttling mechanism in the browser WASM loader. The main changes include renaming the "webcil10" asset behavior to "webcil", splitting the old noThrottleNoRetry map into separate noRetry and noBuffer maps, and restructuring throttling logic to better handle assets that don't buffer immediately (such as dotnetwasm, webcil, and symbols).

Changes:

• Renamed "webcil10" to "webcil" (breaking API change) in public-api.ts and dotnet.d.ts
• Added priority field to AssetEntryInternal for potential future priority-based download handling
• Refactored fetchWasm to fetchMainWasm and restructured throttling logic with new enterThrottling() and leaveThrottling() helper functions
• Split old noThrottleNoRetry map into noRetry (for disabling retries) and noBuffer (for skipping immediate buffering)
• Added try-finally blocks to fetch functions for better error handling and resource cleanup

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/native/libs/Common/JavaScript/types/public-api.ts	Renamed "webcil10" to "webcil" in AssetBehaviors type (breaking change)
src/native/libs/Common/JavaScript/types/internal.ts	Added optional priority field to AssetEntryInternal for throttling bypass
src/native/libs/Common/JavaScript/loader/run.ts	Updated import and call from fetchWasm to fetchMainWasm
src/native/libs/Common/JavaScript/loader/dotnet.d.ts	Renamed "webcil10" to "webcil" in type definitions (breaking change)
src/native/libs/Common/JavaScript/loader/assets.ts	Major refactoring: renamed fetchWasm to fetchMainWasm, extracted enterThrottling/leaveThrottling helpers, split noThrottleNoRetry into noRetry and noBuffer maps, added try-finally blocks for error handling, and updated webcil10 references to webcil

[Copilot]

Critical bug: leaveThrottling() is being called unconditionally here for all assets, but it's also called again for noBuffer assets (dotnetwasm, symbols, webcil) when their response bodies are consumed later. This causes double-decrement of currentParallelDownloads:

• dotnetwasm: decremented here, then again in instantiateMainWasm (line 77)
• webcil: decremented here, then again in fetchDll (line 128)
• symbols: decremented here, then again in fetchNativeSymbols (line 283)

This will make the throttling counter incorrect and potentially negative. The fix is to only call leaveThrottling() here if !noBuffer[asset.behavior], so that noBuffer assets can leave throttling when their response body is actually consumed.

Suggested change

	leaveThrottling();
	if (!noBuffer[asset.behavior]) {
	leaveThrottling();
	}

[Copilot]

The priority field is checked here to allow priority assets to bypass throttling, but this field is never actually set anywhere in the codebase. This means the priority bypass feature is not functional. Either remove this check or add logic to set priority on relevant assets.

Suggested change

	while (throttlingPCS && !asset.priority) {
	while (throttlingPCS) {

[Copilot]

This is a breaking API change. Renaming "webcil10" to "webcil" will break any code that references the "webcil10" value. If this is intentional (e.g., part of a major version update), ensure this breaking change is documented. If backward compatibility is needed, consider keeping "webcil10" as an alias or documenting a migration path.