[FIR] optimize FirSymbol.resolvedContextReceivers

compiler/fir/tree/src/org/jetbrains/kotlin/fir/symbols/impl/FirCallableSymbol.kt

@@ -40,6 +40,7 @@ abstract class FirCallableSymbol<D : FirCallableDeclaration> : FirBasedSymbol<D>
 
     val resolvedContextReceivers: List<FirContextReceiver>
         get() {
+            if (fir.contextReceivers.isEmpty()) return emptyList()
             lazyResolveToPhase(FirResolvePhase.TYPES)
             return fir.contextReceivers
         }

compiler/fir/tree/src/org/jetbrains/kotlin/fir/symbols/impl/FirClassLikeSymbol.kt

@@ -81,6 +81,7 @@ class FirRegularClassSymbol(classId: ClassId) : FirClassSymbol<FirRegularClass>(
 
     val resolvedContextReceivers: List<FirContextReceiver>
         get() {
+            if (fir.contextReceivers.isEmpty()) return emptyList()
             lazyResolveToPhase(FirResolvePhase.TYPES)
             return fir.contextReceivers
         }