[kpm] serializationUtil.kt: Implement custom ClassLoaderObjectInputStream

Previously used the Gradle implementation, which had an undesirable
fallback for the case of missing classes in the given class loader.

For our tests, we want to ensure that only the specified class loader
is used.

libraries/tools/kotlin-gradle-plugin-idea/src/testFixtures/kotlin/org/jetbrains/kotlin/gradle/kpm/idea/testFixtures/serializationUtil.kt

@@ -1,6 +1,5 @@
 package org.jetbrains.kotlin.gradle.kpm.idea.testFixtures
 
-import org.gradle.internal.io.ClassLoaderObjectInputStream
 import java.io.*
 
 /*
@@ -26,3 +25,10 @@ fun ByteArray.deserialize(classLoader: ClassLoader): Any {
     val objectInputStream = ClassLoaderObjectInputStream(inputStream, classLoader)
     return objectInputStream.use { it.readObject() }
 }
+
+class ClassLoaderObjectInputStream(stream: InputStream?, private val classLoader: ClassLoader) : ObjectInputStream(stream) {
+    @Throws(IOException::class, ClassNotFoundException::class)
+    override fun resolveClass(desc: ObjectStreamClass): Class<*> {
+        return Class.forName(desc.name, false, classLoader)
+    }
+}