[FIR] Add default upper bound to type parameter in fir deserializer

compiler/fir/lightTree/src/org/jetbrains/kotlin/fir/lightTree/converter/ConverterUtil.kt

@@ -11,11 +11,11 @@ import com.intellij.psi.tree.TokenSet
 import org.jetbrains.kotlin.KtNodeType
 import org.jetbrains.kotlin.KtNodeTypes.*
 import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.fir.builder.addDefaultBoundIfNecessary
 import org.jetbrains.kotlin.fir.builder.generateResolvedAccessExpression
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameterContainer
 import org.jetbrains.kotlin.fir.declarations.impl.FirTypeParameterImpl
 import org.jetbrains.kotlin.fir.declarations.impl.FirVariableImpl
+import org.jetbrains.kotlin.fir.declarations.impl.addDefaultBoundIfNecessary
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirVariable

compiler/fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/BaseFirBuilder.kt

@@ -19,6 +19,7 @@ import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.impl.FirErrorFunction
 import org.jetbrains.kotlin.fir.declarations.impl.FirErrorLoop
 import org.jetbrains.kotlin.fir.declarations.impl.FirTypeParameterImpl
+import org.jetbrains.kotlin.fir.declarations.impl.addDefaultBoundIfNecessary
 import org.jetbrains.kotlin.fir.expressions.*
 import org.jetbrains.kotlin.fir.expressions.impl.*
 import org.jetbrains.kotlin.fir.references.FirErrorNamedReference

compiler/fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/ConversionUtils.kt

@@ -128,12 +128,6 @@ fun IElementType.toFirOperation(): FirOperation =
         else -> throw AssertionError(this.toString())
     }
 
-fun FirTypeParameterImpl.addDefaultBoundIfNecessary() {
-    if (bounds.isEmpty()) {
-        bounds += FirImplicitNullableAnyTypeRef(null)
-    }
-}
-
 fun FirExpression.generateNotNullOrOther(
     session: FirSession, other: FirExpression, caseId: String, basePsi: KtElement?
 ): FirWhenExpression {

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/deserialization/FirTypeDeserializer.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.deserialization
 
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.impl.FirTypeParameterImpl
+import org.jetbrains.kotlin.fir.declarations.impl.addDefaultBoundIfNecessary
 import org.jetbrains.kotlin.fir.resolve.toTypeProjection
 import org.jetbrains.kotlin.fir.symbols.*
 import org.jetbrains.kotlin.fir.symbols.impl.FirClassLikeSymbol
@@ -98,6 +99,7 @@ class FirTypeDeserializer(
                 proto.upperBoundList.mapTo(bounds) {
                     FirResolvedTypeRefImpl(null, type(it), emptyList())
                 }
+                addDefaultBoundIfNecessary()
             }
         }
     }

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirTypeParameterImpl.kt

@@ -31,7 +31,8 @@ class FirTypeParameterImpl(
 
     /*
      * Note that each type parameter have to has at least one upper bound (Any? if there is no other bounds)
-     *   so if you create FirTypeParameterImpl you need to guarantee this contract
+     *   so after initializing FirTypeParameterImpl you should call [addDefaultBoundIfNecessary] to guarantee
+     *   this contract
      */
     override val bounds: MutableList<FirTypeRef> = mutableListOf()
 
@@ -41,3 +42,9 @@ class FirTypeParameterImpl(
         return super<FirAbstractNamedAnnotatedDeclaration>.transformChildren(transformer, data)
     }
 }
+
+fun FirTypeParameterImpl.addDefaultBoundIfNecessary() {
+    if (bounds.isEmpty()) {
+        bounds += FirImplicitNullableAnyTypeRef(null)
+    }
+}