Support directly invoking interface default methods

With the Java 8 Language one is allowed to directly call default
interface methods of interfaces one (directly) implements through the
use of the super keyword. We support this behavior through the
invoke-super opcode with the target being an interface.

We add 3 tests for this behavior.

Currently only supports slow-path interpreter.

Invoke-super is currently extremely slow.

Bug: 24618811

Change-Id: I7e06e17326f7dbae0116bd7dfefca151f0092bd2
diff --git a/runtime/art_method-inl.h b/runtime/art_method-inl.h
index cf548ad..a5f5c49 100644
--- a/runtime/art_method-inl.h
+++ b/runtime/art_method-inl.h
@@ -225,8 +225,7 @@
     }
     case kSuper:
       // Constructors and static methods are called with invoke-direct.
-      // Interface methods cannot be invoked with invoke-super.
-      return IsConstructor() || IsStatic() || GetDeclaringClass()->IsInterface();
+      return IsConstructor() || IsStatic();
     case kInterface: {
       mirror::Class* methods_class = GetDeclaringClass();
       return IsDirect() || !(methods_class->IsInterface() || methods_class->IsObjectClass());