Merge remote-tracking branch 'origin/2.4' into merge-2.4

Conflicts:
	modules/core/include/opencv2/core/version.hpp
	modules/ocl/include/opencv2/ocl/ocl.hpp
	modules/ocl/src/initialization.cpp
	modules/ocl/test/main.cpp
	modules/superres/CMakeLists.txt
	modules/superres/src/input_array_utility.cpp
	modules/superres/src/input_array_utility.hpp
	modules/superres/src/optical_flow.cpp

modules/ts/include/opencv2/ts.hpp

@@ -551,6 +551,13 @@ int main(int argc, char **argv) \
     return RUN_ALL_TESTS(); \
 }
 
+// This usually only makes sense in perf tests with several implementations,
+// some of which are not available.
+#define CV_TEST_FAIL_NO_IMPL() do { \
+    ::testing::Test::RecordProperty("custom_status", "noimpl"); \
+    FAIL() << "No equivalent implementation."; \
+} while (0)
+
 #endif
 
 #include "opencv2/ts/ts_perf.hpp"