Rename GeneratedClearManagedSource to correct name

src/libraries/System.Runtime.InteropServices/gen/Microsoft.Interop.SourceGeneration/Marshalling/ElementsMarshalling.cs

@@ -28,7 +28,7 @@ protected ElementsMarshalling(IElementsMarshallingCollectionSource collectionSou
             CollectionSource = collectionSource;
         }
 
-        public StatementSyntax GenerateClearManagedSource(TypePositionInfo info, StubCodeContext context)
+        public StatementSyntax GenerateClearUnmanagedDestination(TypePositionInfo info, StubCodeContext context)
         {
             // <GetUnmanagedValuesDestination>.Clear();
             return ExpressionStatement(

src/libraries/System.Runtime.InteropServices/gen/Microsoft.Interop.SourceGeneration/Marshalling/StatefulMarshallingStrategy.cs

@@ -438,7 +438,7 @@ public IEnumerable<StatementSyntax> GenerateMarshalStatements(TypePositionInfo i
             {
                 // If the parameter is marshalled by-value [Out], then we don't marshal the contents of the collection.
                 // We do clear the span, so that if the invoke target doesn't fill it, we aren't left with undefined content.
-                yield return _elementsMarshalling.GenerateClearManagedSource(info, context);
+                yield return _elementsMarshalling.GenerateClearUnmanagedDestination(info, context);
                 yield break;
             }
             if (context.Direction == MarshalDirection.UnmanagedToManaged && !info.IsByRef && info.ByValueContentsMarshalKind.HasFlag(ByValueContentsMarshalKind.Out))

src/libraries/System.Runtime.InteropServices/gen/Microsoft.Interop.SourceGeneration/Marshalling/StatelessMarshallingStrategy.cs

@@ -673,7 +673,7 @@ public IEnumerable<StatementSyntax> GenerateMarshalStatements(TypePositionInfo i
             {
                 // If the parameter is marshalled by-value [Out], then we don't marshal the contents of the collection.
                 // We do clear the span, so that if the invoke target doesn't fill it, we aren't left with undefined content.
-                yield return _elementsMarshalling.GenerateClearManagedSource(info, context);
+                yield return _elementsMarshalling.GenerateClearUnmanagedDestination(info, context);
                 yield break;
             }