Kotlin: Fix getFileClassFqName for IrField

Author: igfoo

java/kotlin-extractor/src/main/kotlin/utils/versions/v_1_7_0/getFileClassFqName.kt

@@ -2,13 +2,25 @@ package com.github.codeql.utils.versions
 
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.ir.declarations.IrDeclaration
+import org.jetbrains.kotlin.ir.declarations.IrField
 import org.jetbrains.kotlin.ir.declarations.IrMemberWithContainerSource
 import org.jetbrains.kotlin.load.kotlin.FacadeClassSource
 
 fun getFileClassFqName(d: IrDeclaration): FqName? {
     // d is in a file class.
     // Get the name in a similar way to the compiler's ExternalPackageParentPatcherLowering
     // visitMemberAccess/generateOrGetFacadeClass.
+
+    // But first, fields aren't IrMemberWithContainerSource, so we need
+    // to get back to the property (if there is one)
+    if (d is IrField) {
+        val propSym = d.correspondingPropertySymbol
+        if (propSym != null) {
+            return getFileClassFqName(propSym.owner)
+        }
+    }
+
+    // Now the main code
     if (d is IrMemberWithContainerSource) {
         val containerSource = d.containerSource
         if (containerSource is FacadeClassSource) {