K2: drop unclear field.initializerResolved check for delegate fields & enums

The property FirVariable.initializerResolved had two problems: in fact,
it was 'initializerHasResolvedType' with no guarantees that the WHOLE
initializer was resolved, and additional check on error expression
making the semantics quite unclear. With return or comparison expressions
as initializer (maybe other cases were possible) this provoked
an exception from KT-82466 as such kind of expression has resolved type
from the beginning (e.g. Nothing) and their children could remain
unresolved for delegate fields.

In this commit I dropped the questionable initializerResolved checks
for delegate fields & enum entries. Both places don't influence our
tests and possible performance impact is also questionable because of
'if (implicitTypeOnly)' check before.

#KT-82466 Fixed

Author: mglukhikh

compiler/fir/analysis-tests/testData/resolve/checkers/delegationWithReturn.fir.fail

@@ -4,4 +4,9 @@
 interface Base
 class Derived: Base
 
-class C(val k: Derived): Base by return k
+class C(val k: Derived): Base by <!RETURN_NOT_ALLOWED!>return<!> k
+
+class D(val k: Derived): Base by <!TYPE_MISMATCH!>k <!UNRESOLVED_REFERENCE!><<!> <!RETURN_NOT_ALLOWED!>return<!> k<!>
+
+/* GENERATED_FIR_TAGS: classDeclaration, inheritanceDelegation, interfaceDeclaration, primaryConstructor,
+propertyDeclaration */

compiler/fir/analysis-tests/testData/resolve/checkers/delegationWithReturn.kt

@@ -54,6 +54,7 @@ import org.jetbrains.kotlin.fir.symbols.impl.FirValueParameterSymbol
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.fir.types.builder.buildErrorTypeRef
 import org.jetbrains.kotlin.fir.types.builder.buildResolvedTypeRef
+import org.jetbrains.kotlin.fir.types.hasResolvedType
 import org.jetbrains.kotlin.fir.utils.exceptions.withFirEntry
 import org.jetbrains.kotlin.fir.visitors.FirTransformer
 import org.jetbrains.kotlin.fir.visitors.transformSingle
@@ -120,7 +121,7 @@ open class FirDeclarationsResolveTransformer(
     }
 
     override fun transformEnumEntry(enumEntry: FirEnumEntry, data: ResolutionMode): FirEnumEntry {
-        if (implicitTypeOnly || enumEntry.initializerResolved) return enumEntry
+        if (implicitTypeOnly) return enumEntry
         return context.withEnumEntry(enumEntry) {
             (enumEntry.transformChildren(this, data) as FirEnumEntry)
         }
@@ -301,7 +302,6 @@ open class FirDeclarationsResolveTransformer(
     override fun transformField(field: FirField, data: ResolutionMode): FirField = whileAnalysing(session, field) {
         val returnTypeRef = field.returnTypeRef
         if (implicitTypeOnly) return field
-        if (field.initializerResolved) return field
 
         dataFlowAnalyzer.enterField(field)
         return withFullBodyResolve {
@@ -1638,12 +1638,6 @@ open class FirDeclarationsResolveTransformer(
     }
 
 
-    private val FirVariable.initializerResolved: Boolean
-        get() {
-            val initializer = initializer ?: return false
-            return initializer.hasResolvedType && initializer !is FirErrorExpression
-        }
-
     private val FirFunction.bodyResolved: Boolean
         get() = body?.hasResolvedType == true
 }