Avoid using bound class reference

Bound references require kotlin-reflect 1.1.x on runtime.
However old Gradle versions (e.g. 3.4) can leak 1.0.x reflect
into Gradle classloader, so getting bound reference fails on runtime
(in this case the plugin couldn't connect to the daemon).

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/compilerRunner/GradleKotlinCompilerRunner.kt

@@ -339,7 +339,7 @@ internal class GradleCompilerRunner(private val project: Project) : KotlinCompil
     private fun logFinish(strategy: String) = log.logFinish(strategy)
 
     override fun getDaemonConnection(environment: GradleCompilerEnvironment): CompileServiceSession? {
-        synchronized(this::javaClass) {
+        synchronized(this.javaClass) {
             val compilerId = CompilerId.makeCompilerId(environment.compilerFullClasspath)
             val clientIsAliveFlagFile = getOrCreateClientFlagFile(project)
             val sessionIsAliveFlagFile = getOrCreateSessionFlagFile(project)