COMPMID-503: Move MinMaxLocation to new validation

Change-Id: I2d518b3a3f15e2c4786488593dac244c1d74a0f9
Reviewed-on: http://mpd-gerrit.cambridge.arm.com/86533
Tested-by: Kaizen <jeremy.johnson+kaizengerrit@arm.com>
Reviewed-by: Moritz Pflanzer <moritz.pflanzer@arm.com>
diff --git a/tests/CL/CLArrayAccessor.h b/tests/CL/CLArrayAccessor.h
index a38907d..a516a9d 100644
--- a/tests/CL/CLArrayAccessor.h
+++ b/tests/CL/CLArrayAccessor.h
@@ -60,7 +60,7 @@
         _array.unmap();
     }
 
-    int num_values() const override
+    size_t num_values() const override
     {
         return _array.num_values();
     }
@@ -75,6 +75,13 @@
         _array.resize(num);
     }
 
+    T &at(size_t index) const override
+    {
+        ARM_COMPUTE_ERROR_ON(_array.buffer() == nullptr);
+        ARM_COMPUTE_ERROR_ON(index >= num_values());
+        return _array.buffer()[index];
+    }
+
 private:
     CLArray<T> &_array;
 };