[openni2]Add warning message when cannot find NETFXSDK. (microsoft#7809)

* [openni2]Add warning message when cannot find NETFXSDK.

* [openni2]Move warning at top.

ports/openni2/CONTROL

@@ -1,5 +1,5 @@
 Source: openni2
-Version: 2.2.0.33-9
+Version: 2.2.0.33-10
 Build-Depends: kinectsdk1
 Homepage: https://github.com/OpenNI/OpenNI2
 Description: OpenNI is open source library for access to Natural Interaction (NI) devices such as RGB-D camera.

ports/openni2/portfile.cmake

@@ -1,8 +1,15 @@
 include(vcpkg_common_functions)
+
 if (VCPKG_CMAKE_SYSTEM_NAME STREQUAL "WindowsStore")
     message(FATAL_ERROR "Error: UWP builds are currently not supported.")
 endif()
 
+find_path(COR_H_PATH cor.h)
+if(COR_H_PATH MATCHES "NOTFOUND")
+    message(FATAL_ERROR "Could not find <cor.h>. Ensure the NETFXSDK is installed.")
+endif()
+get_filename_component(NETFXSDK_PATH "${COR_H_PATH}/../.." ABSOLUTE)
+
 vcpkg_check_linkage(ONLY_DYNAMIC_LIBRARY ONLY_DYNAMIC_CRT)
 
 vcpkg_from_github(
@@ -11,13 +18,9 @@ vcpkg_from_github(
     REF 2.2-beta2
     SHA512 60a3a3043679f3069aea869e92dc5881328ce4393d4140ea8d089027321ac501ae27d283657214e2834d216d0d49bf4f29a4b3d3e43df27a6ed21f889cd0083f
     HEAD_REF master
-)
-
-vcpkg_apply_patches(
-    SOURCE_PATH ${SOURCE_PATH}
-    PATCHES "${CMAKE_CURRENT_LIST_DIR}/upgrade_projects.patch"
-            "${CMAKE_CURRENT_LIST_DIR}/inherit_from_parent_or_project_defaults.patch"
-            "${CMAKE_CURRENT_LIST_DIR}/replace_environment_variable.patch"
+    PATCHES upgrade_projects.patch
+            inherit_from_parent_or_project_defaults.patch
+            replace_environment_variable.patch
 )
 
 file(REMOVE_RECURSE ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET})
@@ -34,6 +37,7 @@ configure_file("${SOURCE_PATH}/Source/Drivers/Kinect/Kinect.vcxproj" "${SOURCE_P
 # Build OpenNI2
 vcpkg_build_msbuild(
     PROJECT_PATH "${SOURCE_PATH}/OpenNI.sln"
+    OPTIONS "/p:DotNetSdkRoot=${NETFXSDK_PATH}/"
 )
 
 # Install OpenNI2