[stdlib] Adopt @_inheritActorContext(always) on Task.immediate

This change aligns implementation with the current SE-0472 proposal.

Author: xedin

stdlib/public/Concurrency/Task+immediate.swift.gyb

@@ -38,9 +38,9 @@ extension Task where Failure == ${FAILURE_TYPE} {
   public static func startSynchronously(
     name: String? = nil,
     priority: TaskPriority? = nil,
-    @_implicitSelfCapture _ operation: __owned @isolated(any) @escaping () async throws -> Success
+    @_inheritActorContext(always) _ operation: sending @isolated(any) @escaping () async throws -> Success
   ) -> Task<Success, ${FAILURE_TYPE}> {
-    immediate(name: name, priority: priority, operation)
+    immediate(name: name, priority: priority, operation: operation)
   }
 
   /// Create and immediately start running a new task in the context of the calling thread/task.
@@ -72,7 +72,7 @@ extension Task where Failure == ${FAILURE_TYPE} {
     priority: TaskPriority? = nil,
     % # NOTE: This closure cannot be 'sending' because we'll trigger ' pattern that the region based isolation checker does not understand how to check'
     % #       In this case: `func syncOnMyGlobalActor() { Task.immediate { @MyGlobalActor in } }`
-    @_implicitSelfCapture _ operation: __owned @isolated(any) @escaping () async throws -> Success
+    @_inheritActorContext(always) operation: sending @isolated(any) @escaping () async throws -> Success
   ) -> Task<Success, ${FAILURE_TYPE}> {
 
     let builtinSerialExecutor =

test/Concurrency/Runtime/startImmediately.swift

@@ -1,6 +1,3 @@
-// FIXME: Marking this disabled since we're reworking the semantics and the test is a bit racy until we do
-// REQUIRES: rdar149506152
-
 // RUN: %empty-directory(%t)
 // RUN: %target-build-swift -Xfrontend -disable-availability-checking %s %import-libdispatch -swift-version 6 -o %t/a.out
 // RUN: %target-codesign %t/a.out

test/abi/macOS/arm64/concurrency.swift

@@ -396,8 +396,8 @@ Added: _$sScTss5NeverORs_rlE18startSynchronously4name8priority_ScTyxABGSSSg_ScPS
 Added: _$sScG16addImmediateTask4name8priority9operationySSSg_ScPSgxyYaYAcntF
 Added: _$sScg31addImmediateTaskUnlessCancelled4name8priority9operationySSSg_ScPSgxyYaKYAcntF
 Added: _$sScG31addImmediateTaskUnlessCancelled4name8priority9operationySSSg_ScPSgxyYaYAcntF
-Added: _$sScTss5NeverORs_rlE9immediate4name8priority_ScTyxABGSSSg_ScPSgxyYaKYAcntFZ
-Added: _$sScTss5Error_pRs_rlE9immediate4name8priority_ScTyxsAA_pGSSSg_ScPSgxyYaKYAcntFZ
+Added: _$sScTss5NeverORs_rlE9immediate4name8priority9operationScTyxABGSSSg_ScPSgxyYaKYAcntFZ
+Added: _$sScTss5Error_pRs_rlE9immediate4name8priority9operationScTyxsAA_pGSSSg_ScPSgxyYaKYAcntFZ
 Added: _$sScg16addImmediateTask4name8priority9operationySSSg_ScPSgxyYaKYAcntF
 Added: _$ss19DiscardingTaskGroupV012addImmediateB04name8priority9operationySSSg_ScPSgyyYaYAcntF
 Added: _$ss19DiscardingTaskGroupV012addImmediateB15UnlessCancelled4name8priority9operationySSSg_ScPSgyyYaYAcntF

test/abi/macOS/x86_64/concurrency.swift

@@ -396,8 +396,8 @@ Added: _$sScTss5NeverORs_rlE18startSynchronously4name8priority_ScTyxABGSSSg_ScPS
 Added: _$sScG16addImmediateTask4name8priority9operationySSSg_ScPSgxyYaYAcntF
 Added: _$sScg31addImmediateTaskUnlessCancelled4name8priority9operationySSSg_ScPSgxyYaKYAcntF
 Added: _$sScG31addImmediateTaskUnlessCancelled4name8priority9operationySSSg_ScPSgxyYaYAcntF
-Added: _$sScTss5NeverORs_rlE9immediate4name8priority_ScTyxABGSSSg_ScPSgxyYaKYAcntFZ
-Added: _$sScTss5Error_pRs_rlE9immediate4name8priority_ScTyxsAA_pGSSSg_ScPSgxyYaKYAcntFZ
+Added: _$sScTss5NeverORs_rlE9immediate4name8priority9operationScTyxABGSSSg_ScPSgxyYaKYAcntFZ
+Added: _$sScTss5Error_pRs_rlE9immediate4name8priority9operationScTyxsAA_pGSSSg_ScPSgxyYaKYAcntFZ
 Added: _$sScg16addImmediateTask4name8priority9operationySSSg_ScPSgxyYaKYAcntF
 Added: _$ss19DiscardingTaskGroupV012addImmediateB04name8priority9operationySSSg_ScPSgyyYaYAcntF
 Added: _$ss19DiscardingTaskGroupV012addImmediateB15UnlessCancelled4name8priority9operationySSSg_ScPSgyyYaYAcntF