[stdlib] Add workaround for unexpected ManagedBuffer ABI mismatch

The missing symbols aren’t load bearing, so this should be fine as a temporary workaround.

Author: lorentey

test/abi/macOS/arm64/stdlib.swift

@@ -245,6 +245,16 @@ Added: _$sSR7isEmptySbvpMV
 // property descriptor for Swift.UnsafeMutableBufferPointer.isEmpty : Swift.Bool
 Added: _$sSr7isEmptySbvpMV
 
+// Mangling issue with the generalized `ManagedBuffer`'s dummy initializer. (rdar://124644596)
+// dispatch thunk of Swift.ManagedBuffer.__allocating_init(_doNotCallMe: ()) -> Swift.ManagedBuffer<A, B>
+Removed: _$ss13ManagedBufferC12_doNotCallMeAByxq_Gyt_tcfCTj
+// method descriptor for Swift.ManagedBuffer.__allocating_init(_doNotCallMe: ()) -> Swift.ManagedBuffer<A, B>
+Removed: _$ss13ManagedBufferC12_doNotCallMeAByxq_Gyt_tcfCTq
+// dispatch thunk of (extension in Swift):Swift.ManagedBuffer< where B: ~Swift.Copyable>.init(_doNotCallMe: ()) -> Swift.ManagedBuffer<A, B>
+Added: _$ss13ManagedBufferCsRic_rlE12_doNotCallMeAByxq_Gyt_tcfCTj
+// method descriptor for (extension in Swift):Swift.ManagedBuffer< where B: ~Swift.Copyable>.init(_doNotCallMe: ()) -> Swift.ManagedBuffer<A, B>
+Added: _$ss13ManagedBufferCsRic_rlE12_doNotCallMeAByxq_Gyt_tcfCTq
+
 // Runtime Symbols
 Added: __swift_pod_copy
 Added: __swift_pod_destroy

test/abi/macOS/x86_64/stdlib.swift

@@ -245,6 +245,16 @@ Added: _$sSR7isEmptySbvpMV
 // property descriptor for Swift.UnsafeMutableBufferPointer.isEmpty : Swift.Bool
 Added: _$sSr7isEmptySbvpMV
 
+// Mangling issue with the generalized `ManagedBuffer`'s dummy initializer. (rdar://124644596)
+// dispatch thunk of Swift.ManagedBuffer.__allocating_init(_doNotCallMe: ()) -> Swift.ManagedBuffer<A, B>
+Removed: _$ss13ManagedBufferC12_doNotCallMeAByxq_Gyt_tcfCTj
+// method descriptor for Swift.ManagedBuffer.__allocating_init(_doNotCallMe: ()) -> Swift.ManagedBuffer<A, B>
+Removed: _$ss13ManagedBufferC12_doNotCallMeAByxq_Gyt_tcfCTq
+// dispatch thunk of (extension in Swift):Swift.ManagedBuffer< where B: ~Swift.Copyable>.init(_doNotCallMe: ()) -> Swift.ManagedBuffer<A, B>
+Added: _$ss13ManagedBufferCsRic_rlE12_doNotCallMeAByxq_Gyt_tcfCTj
+// method descriptor for (extension in Swift):Swift.ManagedBuffer< where B: ~Swift.Copyable>.init(_doNotCallMe: ()) -> Swift.ManagedBuffer<A, B>
+Added: _$ss13ManagedBufferCsRic_rlE12_doNotCallMeAByxq_Gyt_tcfCTq
+
 // Runtime Symbols
 Added: __swift_pod_copy
 Added: __swift_pod_destroy