Adds tests to verify proper marshaling of vectors of interface types.

Bug: 30570663
Test: hidl_test
Change-Id: I1e4d1f826773abbde6b9019eb6af90ac64007e38
diff --git a/tests/foo/1.0/IFoo.hal b/tests/foo/1.0/IFoo.hal
index 614f1e4..b6ef5c8 100644
--- a/tests/foo/1.0/IFoo.hal
+++ b/tests/foo/1.0/IFoo.hal
@@ -18,6 +18,7 @@
 
 import IFooCallback;
 import IMyTypes.SomeStruct;
+import ISimple;
 import ITheirTypes.FloatArray;
 
 interface IFoo {
@@ -107,4 +108,9 @@
     sendVec(vec<uint8_t> data) generates (vec<uint8_t> data);
 
     sendVecVec() generates (vec<vec<uint8_t>> vecvec);
+
+    haveAVectorOfInterfaces(vec<ISimple> in) generates (vec<ISimple> out);
+
+    haveAVectorOfGenericInterfaces(vec<interface> in)
+        generates (vec<interface> out);
 };