[FIR] Fully expand the bounds of type parameters for canBeNull check

This is required because a not-null bound `Foo` can resolve to a
`typealias Foo = Bar?` in which case we must return true.

#KT-64645 Fixed

analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/components/KtFirTypeInfoProvider.kt

@@ -35,7 +35,7 @@ internal class KtFirTypeInfoProvider(
         return (type as KtFirType).coneType.functionTypeKind(analysisSession.useSiteSession)
     }
 
-    override fun canBeNull(type: KtType): Boolean = (type as KtFirType).coneType.canBeNull
+    override fun canBeNull(type: KtType): Boolean = (type as KtFirType).coneType.canBeNull(analysisSession.useSiteSession)
 
     override fun isDenotable(type: KtType): Boolean {
         val coneType = (type as KtFirType).coneType

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java

@@ -35179,6 +35179,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
                     runTest("compiler/testData/diagnostics/tests/smartCasts/castchecks/insideCall.kt");
                 }
 
+                @Test
+                @TestMetadata("kt64645.kt")
+                public void testKt64645() throws Exception {
+                    runTest("compiler/testData/diagnostics/tests/smartCasts/castchecks/kt64645.kt");
+                }
+
                 @Test
                 @TestMetadata("smartCastOfNullableExpressionWithExpectedType.kt")
                 public void testSmartCastOfNullableExpressionWithExpectedType() throws Exception {

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java

@@ -35179,6 +35179,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
                     runTest("compiler/testData/diagnostics/tests/smartCasts/castchecks/insideCall.kt");
                 }
 
+                @Test
+                @TestMetadata("kt64645.kt")
+                public void testKt64645() throws Exception {
+                    runTest("compiler/testData/diagnostics/tests/smartCasts/castchecks/kt64645.kt");
+                }
+
                 @Test
                 @TestMetadata("smartCastOfNullableExpressionWithExpectedType.kt")
                 public void testSmartCastOfNullableExpressionWithExpectedType() throws Exception {