COMPMID-424 Add CL validation tests for Box3x3

* Add tests for different border modes
* Add padding calculator

Change-Id: Ic4708faddfb1c8e6b59d349cf9cb48c9a181d717
Reviewed-on: http://mpd-gerrit.cambridge.arm.com/78105
Tested-by: Kaizen <jeremy.johnson+kaizengerrit@arm.com>
Reviewed-by: Moritz Pflanzer <moritz.pflanzer@arm.com>
diff --git a/tests/validation/ReferenceCPP.h b/tests/validation/ReferenceCPP.h
index b5e3fa0..aeafa76 100644
--- a/tests/validation/ReferenceCPP.h
+++ b/tests/validation/ReferenceCPP.h
@@ -145,12 +145,14 @@
      * @param[out] dst Result tensor.
      */
     static void bitwise_not(const RawTensor &src, RawTensor &dst);
-    /** Function to compute 3-by-3 box filtered result tensor.
+    /** Function to compute box3x3 filtered result tensor.
      *
-     * @param[in]  src Input tensor.
-     * @param[out] dst Result tensor.
+     * @param[in]  src                   Input tensor.
+     * @param[out] dst                   Result tensor.
+     * @param[in]  border_mode           Border mode.
+     * @param[in]  constant_border_value Constant border value if @p border_mode is BorderMode::CONSTANT.
      */
-    static void box3x3(const RawTensor &src, RawTensor &dst);
+    static void box3x3(const RawTensor &src, RawTensor &dst, BorderMode border_mode, uint8_t constant_border_value);
     /** Depth conversion from @p src to @p dst
      *
      * @param[in]  src    First tensor.