[Stubs] Fix stub inconsistency on unnamed setter parameters

If an unused setter parameter was replaced with an underscore ('_'),
it had a special name in the stub ('<anonymous parameter 0>'). The text
version of the stub inserted it as is, leading to an extra
'PsiErrorElement'.

^KTIJ-28194 Fixed

analysis/decompiled/decompiler-native/tests/org/jetbrains/kotlin/analysis/decompiler/konan/DecompiledKnmStubConsistencyFe10TestGenerated.java

@@ -311,4 +311,10 @@ public class DecompiledKnmStubConsistencyFe10TestGenerated extends AbstractDecom
     public void testTypes() throws Exception {
         runTest("analysis/decompiled/decompiler-to-file-stubs/testData/clsFileStubBuilder/Types/");
     }
+
+    @Test
+    @TestMetadata("UnderscoreParameterName")
+    public void testUnderscoreParameterName() throws Exception {
+        runTest("analysis/decompiled/decompiler-to-file-stubs/testData/clsFileStubBuilder/UnderscoreParameterName/");
+    }
 }

analysis/decompiled/decompiler-native/tests/org/jetbrains/kotlin/analysis/decompiler/konan/DecompiledKnmStubConsistencyK2TestGenerated.java

@@ -311,4 +311,10 @@ public class DecompiledKnmStubConsistencyK2TestGenerated extends AbstractDecompi
     public void testTypes() throws Exception {
         runTest("analysis/decompiled/decompiler-to-file-stubs/testData/clsFileStubBuilder/Types/");
     }
+
+    @Test
+    @TestMetadata("UnderscoreParameterName")
+    public void testUnderscoreParameterName() throws Exception {
+        runTest("analysis/decompiled/decompiler-to-file-stubs/testData/clsFileStubBuilder/UnderscoreParameterName/");
+    }
 }