Fix KClassImpl#toString to render Kotlin FQ name, not JVM one

compiler/testData/codegen/boxWithStdlib/reflection/methodsFromAny/classToString.kt

@@ -1,14 +1,26 @@
 import kotlin.test.*
-import kotlin.reflect.jvm.kotlin
 
-class A
+class A {
+    class Nested
+
+    companion object
+}
 
 fun box(): String {
-    val p = javaClass<A>().kotlin
-    if ("$p" != "class A") return "Fail: $p"
+    assertEquals("class A", "${A::class}")
+    assertEquals("class A\$Nested", "${A.Nested::class}")
+    assertEquals("class A\$Companion", "${A.Companion::class}")
 
-    val s = javaClass<String>().kotlin
-    if ("$s" != "class java.lang.String") return "Fail: $s"
+    assertEquals("class kotlin.Any", "${Any::class}")
+    assertEquals("class kotlin.Int", "${Int::class}")
+    assertEquals("class kotlin.Int\$Companion", "${Int.Companion::class}")
+    assertEquals("class kotlin.IntArray", "${IntArray::class}")
+    // TODO
+    // assertEquals("class kotlin.Array", "${Array<Any>::class}")
+    assertEquals("class kotlin.String", "${String::class}")
+    assertEquals("class kotlin.String", "${java.lang.String::class}")
+
+    assertEquals("class java.lang.Runnable", "${Runnable::class}")
 
     return "OK"
 }

core/reflection.jvm/src/kotlin/reflect/jvm/internal/KClassImpl.kt

@@ -102,6 +102,12 @@ class KClassImpl<T>(override val jClass: Class<T>) : KCallableContainerImpl(), K
     override fun hashCode(): Int =
             jClass.hashCode()
 
-    override fun toString(): String =
-            jClass.toString()
+    override fun toString(): String {
+        return "class " + classId.let { classId ->
+            val packageFqName = classId.getPackageFqName()
+            val packagePrefix = if (packageFqName.isRoot()) "" else packageFqName.asString() + "."
+            val classSuffix = classId.getRelativeClassName().asString().replace('.', '$')
+            packagePrefix + classSuffix
+        }
+    }
 }