Add test case t10290

Author: liufengyun

tests/run/t10290.scala

@@ -0,0 +1,28 @@
+trait A1 {
+  private val s = "A1"
+  def f = s
+}
+
+trait A2 {
+  private val s = "A2"
+  def f = s
+}
+
+class B extends A1 with A2 {
+  override def f = "B"
+  class C {
+    def t1 = B.super[A1].f
+    def t2 = B.super[A2].f
+    def t3 = B.this.f
+  }
+}
+
+object Test {
+  def main(args : Array[String]) : Unit = {
+    val b = new B
+    val c = new b.C
+    assert(c.t1 == "A1")
+    assert(c.t2 == "A2")
+    assert(c.t3 == "B")
+  }
+}