COMPMID-1478: Stop relying on static default OpenCL objects in cl2.hpp

This causes problems when ACL is used as a shared library on Android.
Fixes some problems related to creation / destruction order between the Graph's CL backend and core / runtime

Change-Id: I716d63fd42f4586df1ffbb6fa97e4db06d3a781b
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/143228
Tested-by: Jenkins <bsgcomp@arm.com>
Reviewed-by: Michele DiGiorgio <michele.digiorgio@arm.com>
Reviewed-by: Gian Marco Iodice <gianmarco.iodice@arm.com>
diff --git a/src/core/CL/kernels/CLHistogramKernel.cpp b/src/core/CL/kernels/CLHistogramKernel.cpp
index 7b715ab..b56ad8d 100644
--- a/src/core/CL/kernels/CLHistogramKernel.cpp
+++ b/src/core/CL/kernels/CLHistogramKernel.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2017 ARM Limited.
+ * Copyright (c) 2016-2018 ARM Limited.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -107,7 +107,7 @@
 
     update_window_and_padding(win, AccessWindowHorizontal(input->info(), 0, pixels_per_item));
 
-    ICLKernel::configure(win);
+    ICLKernel::configure_internal(win);
 }
 
 void CLHistogramKernel::run(const Window &window, cl::CommandQueue &queue)
@@ -198,7 +198,7 @@
     win.set(0, Window::Dimension(start_position, _input->info()->dimension(0)));
     win.set(1, Window::Dimension(0, _input->info()->dimension(1)));
     update_window_and_padding(win, AccessWindowHorizontal(input->info(), 0, 1));
-    ICLKernel::configure(win);
+    ICLKernel::configure_internal(win);
 }
 
 void CLHistogramBorderKernel::run(const Window &window, cl::CommandQueue &queue)