Code quality improvements

Author: tamasvajk

java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt

@@ -1914,13 +1914,6 @@ open class KotlinFileExtractor(
                 unaryopReceiver(id, c.dispatchReceiver, "Dispatch receiver")
             }
 
-            /**
-             * Populate the lhs of a binary op from this call's extension receiver, and the rhs from its sole argument.
-             */
-            fun binopExtensionMethod(id: Label<out DbExpr>) {
-                binopReceiver(id, c.extensionReceiver, "Extension receiver")
-            }
-
             val dr = c.dispatchReceiver
             when {
                 isFunction(target, "kotlin", "String", "plus", false) -> {

java/kotlin-extractor/src/main/kotlin/KotlinUsesExtractor.kt

@@ -1290,7 +1290,7 @@ open class KotlinUsesExtractor(
                             else null
                         } ?: run {
                             val parentFqName = parentClass.fqNameWhenAvailable?.asString()
-                            val msg = "Couldn't find a Java equivalent function to $parentFqName.${f.name} in ${javaClass.fqNameWhenAvailable}"
+                            val msg = "Couldn't find a Java equivalent function to $parentFqName.${f.name.asString()} in ${javaClass.fqNameWhenAvailable?.asString()}"
                             if (!globalExtensionState.deduplicatedWarnings.contains(msg)) {
                                 logger.warn(msg)
                                 globalExtensionState.deduplicatedWarnings.add(msg)

java/kotlin-extractor/src/main/kotlin/utils/Iterable.kt

@@ -12,15 +12,3 @@ inline fun <reified S: IrDeclaration> Iterable<IrDeclaration>.findSubType(
 ): S? {
     return this.find { it is S && predicate(it) } as S?
 }
-
-/**
- * This behaves the same as Iterable<IrDeclaration>.singleOrNull, but
- * requires that the value found is of the subtype S, and it casts
- * the result for you appropriately.
- */
-inline fun <reified S: IrDeclaration> Iterable<IrDeclaration>.singleOrNullSubType(
-    predicate: (S) -> Boolean
-): S? {
-    return this.singleOrNull { it is S && predicate(it) } as S?
-}
-