Merge pull request #15419 from OrestChura:gapi_headers_internal_flag_issue

* - headers in "infer/" and "infer/ie/" folders are included into gapi_ext_hdrs;
+ because of that a few #includes are required in the headers
- HAVE_INF_ENGINE flag check in headers "infer/ie.hpp" and "infer/ie/util.hpp" is deleted

* - the "ie/util.hpp" header is a private header now as it's used for tests; it's been moved to the scr directory to the place next to the implementation file "ie/giebackend.cpp"
- the path to this header in files "ie/giebackend.cpp" and "test/infer/gapi_infer_ie_test.cpp" is updated
- As it's private header now and explicitly depends on IE, the "HAVE_INF_ENGINE" flag check is returned

modules/gapi/CMakeLists.txt

@@ -28,6 +28,7 @@ file(GLOB gapi_ext_hdrs
     "${CMAKE_CURRENT_LIST_DIR}/include/opencv2/${name}/ocl/*.hpp"
     "${CMAKE_CURRENT_LIST_DIR}/include/opencv2/${name}/fluid/*.hpp"
     "${CMAKE_CURRENT_LIST_DIR}/include/opencv2/${name}/own/*.hpp"
+    "${CMAKE_CURRENT_LIST_DIR}/include/opencv2/${name}/infer/*.hpp"
     )
 
 set(gapi_srcs

modules/gapi/include/opencv2/gapi/infer/ie.hpp

@@ -7,8 +7,6 @@
 #ifndef OPENCV_GAPI_INFER_IE_HPP
 #define OPENCV_GAPI_INFER_IE_HPP
 
-#ifdef HAVE_INF_ENGINE
-
 #include <unordered_map>
 #include <string>
 #include <array>
@@ -17,6 +15,9 @@
 #include <opencv2/gapi/opencv_includes.hpp>
 #include <opencv2/gapi/util/any.hpp>
 
+#include <opencv2/core/cvdef.h>     // GAPI_EXPORTS
+#include <opencv2/gapi/gkernel.hpp> // GKernelPackage
+
 namespace cv {
 namespace gapi {
 // FIXME: introduce a new sub-namespace for NN?
@@ -101,6 +102,4 @@ protected:
 } // namespace gapi
 } // namespace cv
 
-#endif // HAVE_INF_ENGINE
-
 #endif // OPENCV_GAPI_INFER_HPP

modules/gapi/src/backends/ie/giebackend.cpp

@@ -28,12 +28,12 @@
 #include <opencv2/gapi/gtype_traits.hpp>
 
 #include <opencv2/gapi/infer.hpp>
-#include <opencv2/gapi/infer/ie/util.hpp>
 
 #include "compiler/gobjref.hpp"
 #include "compiler/gmodel.hpp"
 
 #include "backends/ie/giebackend.hpp"
+#include "backends/ie/util.hpp"
 
 #include "api/gbackend_priv.hpp" // FIXME: Make it part of Backend SDK!
 

modules/gapi/src/backends/ie/util.hpp

@@ -15,6 +15,9 @@
 
 #include "inference_engine.hpp"
 
+#include <opencv2/core/cvdef.h>     // GAPI_EXPORTS
+#include <opencv2/gapi/gkernel.hpp> // GKernelPackage
+
 namespace cv {
 namespace gapi {
 namespace ie {
@@ -27,5 +30,6 @@ GAPI_EXPORTS InferenceEngine::Blob::Ptr to_ie(cv::Mat &blob);
 
 }}}}
 
-#endif // HAVE_INF_ENGINE
+#endif //HAVE_INF_ENGINE
+
 #endif // OPENCV_GAPI_INFER_IE_UTIL_HPP

modules/gapi/test/infer/gapi_infer_ie_test.cpp

@@ -35,7 +35,8 @@
 #include <ade/util/iota_range.hpp>
 
 #include <opencv2/gapi/infer/ie.hpp>
-#include <opencv2/gapi/infer/ie/util.hpp>
+
+#include "backends/ie/util.hpp"
 
 namespace opencv_test
 {