[FIR] Remove duplicated code discovered by running inspection

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirOverrideChecker.kt

@@ -28,9 +28,8 @@ import org.jetbrains.kotlin.fir.originalOrSelf
 import org.jetbrains.kotlin.fir.resolve.substitution.substitutorByMap
 import org.jetbrains.kotlin.fir.resolve.toSymbol
 import org.jetbrains.kotlin.fir.scopes.FirTypeScope
-import org.jetbrains.kotlin.fir.scopes.getDirectOverriddenFunctions
-import org.jetbrains.kotlin.fir.scopes.getDirectOverriddenProperties
 import org.jetbrains.kotlin.fir.scopes.impl.toConeType
+import org.jetbrains.kotlin.fir.scopes.retrieveDirectOverriddenOf
 import org.jetbrains.kotlin.fir.symbols.SymbolInternals
 import org.jetbrains.kotlin.fir.symbols.lazyResolveToPhase
 import org.jetbrains.kotlin.fir.symbols.impl.*
@@ -56,22 +55,6 @@ object FirOverrideChecker : FirClassChecker() {
         }
     }
 
-    private fun FirTypeScope.retrieveDirectOverriddenOf(memberSymbol: FirCallableSymbol<*>): List<FirCallableSymbol<*>> {
-        return when (memberSymbol) {
-            is FirNamedFunctionSymbol -> {
-                processFunctionsByName(memberSymbol.name) {}
-                getDirectOverriddenFunctions(memberSymbol)
-            }
-
-            is FirPropertySymbol -> {
-                processPropertiesByName(memberSymbol.name) {}
-                getDirectOverriddenProperties(memberSymbol)
-            }
-
-            else -> throw IllegalArgumentException("unexpected member kind $memberSymbol")
-        }
-    }
-
     private fun ConeKotlinType.substituteAllTypeParameters(
         overrideDeclaration: FirCallableSymbol<*>,
         baseDeclaration: FirCallableSymbol<*>,

compiler/fir/raw-fir/light-tree2fir/src/org/jetbrains/kotlin/fir/lightTree/converter/LightTreeRawFirExpressionBuilder.kt

@@ -890,21 +890,7 @@ class LightTreeRawFirExpressionBuilder(
             baseSource = whenCondition.toFirSourceElement(),
             operationReferenceSource = conditionSource
         )
-        return if (hasSubject) {
-            WhenConditionConvertedResults(result, false)
-        } else {
-            WhenConditionConvertedResults(
-                buildErrorExpression {
-                    source = whenCondition.toFirSourceElement()
-                    diagnostic = ConeSimpleDiagnostic(
-                        "No expression in condition with expression",
-                        DiagnosticKind.ExpressionExpected
-                    )
-                    nonExpressionElement = result
-                },
-                true,
-            )
-        }
+        return createWhenConditionConvertedResults(hasSubject, result, whenCondition)
     }
 
     private fun convertWhenConditionIsPattern(
@@ -934,6 +920,14 @@ class LightTreeRawFirExpressionBuilder(
             argumentList = buildUnaryArgumentList(subjectExpression)
         }
 
+        return createWhenConditionConvertedResults(hasSubject, result, whenCondition)
+    }
+
+    private fun createWhenConditionConvertedResults(
+        hasSubject: Boolean,
+        result: FirExpression,
+        whenCondition: LighterASTNode,
+    ): WhenConditionConvertedResults {
         return if (hasSubject) {
             WhenConditionConvertedResults(result, false)
         } else {