Fix unit test where NeonMemoryManager was used instead of RefMemoryManager

Although the Neon and Ref backends can use each other's TensorHandles,
their TensorHandleFactories can't use each other's MemoryManagers.
Incorrectly passing the NeonMemoryManager to the RefTensorHandleFactory
in unit test utility code resulted in an incorrect static_pointer_cast
and a warning from the Undefined Behaviour Sanitizer.

This change fixes the test code, and replaces use of static_pointer_cast
with armnn::PolymorphicPointerDowncast which will check that the cast is
legal in debug builds.

Also, remove MockWorkloadFactoryHelper.hpp as it is unused.

Signed-off-by: Matthew Bentham <matthew.bentham@arm.com>
Change-Id: I2b425e86fccacd7cc5ff186521fc6e53e7e50c77

1 files changed, 2 insertions, 1 deletions

diff --git a/src/backends/neon/NeonTimer.cpp b/src/backends/neon/NeonTimer.cpp
index 5cce0511ab..a7d3032b13 100644
--- a/src/backends/neon/NeonTimer.cpp
+++ b/src/backends/neon/NeonTimer.cpp
@@ -7,6 +7,7 @@
 #include "NeonInterceptorScheduler.hpp"
 
 #include <armnn/utility/Assert.hpp>
+#include <armnn/utility/PolymorphicDowncast.hpp>
 
 #include <memory>
 
@@ -29,7 +30,7 @@ void NeonTimer::Start()
     {
         // Keep the real schedule and add NeonInterceptorScheduler as an interceptor
         m_RealScheduler  = &arm_compute::Scheduler::get();
-        arm_compute::Scheduler::set(std::static_pointer_cast<arm_compute::IScheduler>(g_Interceptor));
+        arm_compute::Scheduler::set(armnn::PolymorphicPointerDowncast<arm_compute::IScheduler>(g_Interceptor));
     }
 }