[FIR] Call distinctBy for containsMultipleNonSubsumed

Otherwise, when analyzing
`PsiTypeParameterListOwner` in the
related test, we (after flattening and
`nonSubsumed()`) get 2 `JvmMember.accept`
from the same very java enhancement
scope `JvmMember`.

^KT-65972

compiler/fir/providers/src/org/jetbrains/kotlin/fir/declarations/declarationUtils.kt

@@ -160,6 +160,12 @@ fun MemberWithBaseScope<FirCallableSymbol<*>>.getNonSubsumedOverriddenSymbols():
         .map { it.member }
 }
 
+fun List<MemberWithBaseScope<FirCallableSymbol<*>>>.getNonSubsumedNonPhantomOverriddenSymbols(): List<MemberWithBaseScope<FirCallableSymbol<*>>> {
+    return flatMap { it.flattenPhantomIntersectionsRecursively() }
+        .nonSubsumed()
+        .distinctBy { it.member.unwrapSubstitutionOverrides<FirCallableSymbol<*>>() }
+}
+
 fun FirCallableSymbol<*>.dispatchReceiverScope(session: FirSession, scopeSession: ScopeSession): FirTypeScope {
     val dispatchReceiverType = requireNotNull(dispatchReceiverType)
     return dispatchReceiverType.scope(

compiler/fir/providers/src/org/jetbrains/kotlin/fir/scopes/impl/FirTypeIntersectionScopeContext.kt

@@ -180,8 +180,8 @@ class FirTypeIntersectionScopeContext(
                     overriddenMembers = group,
                     containingScope = null,
                     containsMultipleNonSubsumed = when {
-                        forClassUseSiteScope -> group.flatMap { it.flattenPhantomIntersectionsRecursively() }.nonSubsumed().size > 1
-                        else -> mostSpecific.flatMap { it.flattenPhantomIntersectionsRecursively() }.nonSubsumed().size > 1
+                        forClassUseSiteScope -> group.getNonSubsumedNonPhantomOverriddenSymbols().size > 1
+                        else -> mostSpecific.getNonSubsumedNonPhantomOverriddenSymbols().size > 1
                     },
                 )
             } else {

compiler/testData/diagnostics/tests/intersectionWithMultipleDefaultsInJavaWithAdditionalSymbolsAfterNonSubsumed.fir.kt

@@ -1,29 +0,0 @@
-// FILE: JvmElement.java
-public interface JvmElement {
-    default void accept() {}
-}
-
-// FILE: JvmMember.java
-public interface JvmMember extends JvmElement {
-    default void accept() {}
-}
-
-// FILE: PsiJvmMember.java
-// Provides a phantom IO
-public interface PsiJvmMember extends JvmMember, JvmElement {}
-
-// FILE: PsiTypeParameterListOwner.java
-// Must also provide a phantom IO
-public interface PsiTypeParameterListOwner extends PsiJvmMember, JvmMember {}
-
-// FILE: JvmClass.java
-public interface JvmClass extends JvmMember, JvmElement {
-    default void accept() {}
-}
-
-// FILE: PsiClass.java
-public interface PsiClass extends PsiTypeParameterListOwner, JvmClass {}
-
-// FILE: Main.kt
-
-<!CANNOT_INFER_VISIBILITY!>class K<!> : PsiClass

compiler/testData/diagnostics/tests/intersectionWithMultipleDefaultsInJavaWithAdditionalSymbolsAfterNonSubsumed.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 // FILE: JvmElement.java
 public interface JvmElement {
     default void accept() {}