Add more tests in uncommonCases folder

1) dataClass.kt - test with data class
2) receiver.kt - test with Int extension receiver
3) delegation.kt - test with implementation by delegation

compiler/visualizer/testData/uncommonCases/testFiles/delegation.kt

@@ -0,0 +1,19 @@
+interface Base {
+    fun printMessage()
+    fun printMessageLine()
+}
+
+class BaseImpl(val x: Int) : Base {
+    override fun printMessage() { print(x) }
+    override fun printMessageLine() { println(x) }
+}
+
+class Derived(b: Base) : Base by b {
+    override fun printMessage() { print("abc") }
+}
+
+fun main() {
+    val b = BaseImpl(10)
+    Derived(b).printMessage()
+    Derived(b).printMessageLine()
+}