Adds CustomAllocator interface and Sample App

 * Updates the runtime options with a CustomAllocatorMap which allows to define a CustomAllocator for specific backends
 * Change IBackendInternal interface to use a shared pointer to a custom allocator
 * Update ClBackend.hpp/cpp to use the CustomAllocator
 * Adds an example application and unit test which uses a CustomAllocator for GpuAcc
 * Refactor of the interface to use MemorySource instead of the user Mapping cl_mem directly
 * Modify the BackendRegistry to also hold a registry of CustomAllocators
 * BackendRegistry Deregister will also deregister any allocators associated with that backend id
 * set_global_allocator within the BaseMemoryManager so that it always matches the currently used allocator

Signed-off-by: Jan Eilers <jan.eilers@arm.com>
Change-Id: I156d819686021865f4375e6cb7a5c5dec8fee9e8
Signed-off-by: David Monahan <david.monahan@arm.com>
diff --git a/src/backends/aclCommon/BaseMemoryManager.cpp b/src/backends/aclCommon/BaseMemoryManager.cpp
index 45e0480..c60a4a0 100644
--- a/src/backends/aclCommon/BaseMemoryManager.cpp
+++ b/src/backends/aclCommon/BaseMemoryManager.cpp
@@ -15,7 +15,7 @@
 {
 
 #if defined(ARMCOMPUTENEON_ENABLED) || defined(ARMCOMPUTECL_ENABLED)
-BaseMemoryManager::BaseMemoryManager(std::unique_ptr<arm_compute::IAllocator> alloc,
+BaseMemoryManager::BaseMemoryManager(std::shared_ptr<arm_compute::IAllocator> alloc,
                                      MemoryAffinity memoryAffinity)
 {
     ARMNN_ASSERT(alloc);