Changed type of OPENCV_BUILD_3RDPARTY_LIBS variable to the INTERNAL on WIndows

(see comments for #1030 ticket https://code.ros.org/trac/opencv/ticket/1030)

CMakeLists.txt

@@ -344,7 +344,7 @@ set(BUILD_PERF_TESTS ON CACHE BOOL "Build performance tests")
 # Build 3rdparty libraries under unix
 # ===================================================
 if(WIN32)
-    set(OPENCV_BUILD_3RDPARTY_LIBS TRUE  CACHE BOOL "Build 3rd party libraries")
+    set(OPENCV_BUILD_3RDPARTY_LIBS TRUE  CACHE INTERNAL "Build 3rd party libraries")
 else()
     set(OPENCV_BUILD_3RDPARTY_LIBS FALSE CACHE BOOL "Build 3rd party libraries")
 endif()
@@ -568,34 +568,6 @@ if(UNIX)
       set(HAVE_DC1394 FALSE)
     endif()
 
-    if(NOT OPENCV_BUILD_3RDPARTY_LIBS)
-        include(FindZLIB)
-        if(WITH_PNG)
-            include(FindPNG)
-            if(PNG_FOUND)
-                CHECK_INCLUDE_FILE(${PNG_PNG_INCLUDE_DIR}/png.h HAVE_PNG_H)
-                CHECK_INCLUDE_FILE(${PNG_PNG_INCLUDE_DIR}/libpng/png.h HAVE_LIBPNG_PNG_H)
-            endif()
-        else()
-            set(PNG_FOUND FALSE)
-        endif()
-        if(WITH_TIFF)
-            include(FindTIFF)
-        else()
-            set(TIFF_FOUND FALSE)
-        endif()
-        if(WITH_JASPER)
-            include(FindJasper)
-        else()
-            set(JASPER_FOUND FALSE)
-        endif()
-        if(WITH_JPEG)
-            include(FindJPEG)
-        else()
-            set(JPEG_FOUND FALSE)
-        endif()
-    endif()
-
 	if(NOT APPLE)
         CHECK_INCLUDE_FILE(alloca.h HAVE_ALLOCA_H)
         CHECK_FUNCTION_EXISTS(alloca HAVE_ALLOCA)
@@ -628,6 +600,36 @@ if(UNIX)
         add_definitions(-DHAVE_ALLOCA -DHAVE_ALLOCA_H -DHAVE_LIBPTHREAD -DHAVE_UNISTD_H)
     endif()
 endif()
+if (UNIX OR WIN32)
+	if(NOT OPENCV_BUILD_3RDPARTY_LIBS)
+		message(STATUS "NOT OPENCV_BUILD_3RDPARTY_LIBS **************************************************")
+        include(FindZLIB)
+        if(WITH_PNG)
+            include(FindPNG)
+            if(PNG_FOUND)
+                CHECK_INCLUDE_FILE(${PNG_PNG_INCLUDE_DIR}/png.h HAVE_PNG_H)
+                CHECK_INCLUDE_FILE(${PNG_PNG_INCLUDE_DIR}/libpng/png.h HAVE_LIBPNG_PNG_H)
+            endif()
+        else()
+            set(PNG_FOUND FALSE)
+        endif()
+        if(WITH_TIFF)
+            include(FindTIFF)
+        else()
+            set(TIFF_FOUND FALSE)
+        endif()
+        if(WITH_JASPER)
+            include(FindJasper)
+        else()
+            set(JASPER_FOUND FALSE)
+        endif()
+        if(WITH_JPEG)
+		    include(FindJPEG)
+        else()
+		    set(JPEG_FOUND FALSE)
+        endif()
+    endif()
+endif()
 
 if(WITH_PNG AND NOT PNG_FOUND)
     set(PNG_LIBRARIES libpng)
@@ -1688,7 +1690,7 @@ endif()
 # media
 status("")
 status("  Media I/O: ")
-status("    ZLib:"      ZLIB_FOUND                         THEN YES             ELSE build)
+status("    ZLib:"      ZLIB_FOUND                         THEN ${ZLIB_FOUND}             ELSE build)
 status("    JPEG:"      NOT WITH_JPEG OR JPEG_FOUND        THEN ${JPEG_FOUND}   ELSE build)
 status("    PNG:"       NOT WITH_PNG OR PNG_FOUND          THEN ${PNG_FOUND}    ELSE build)
 status("    TIFF:"      NOT WITH_TIFF OR TIFF_FOUND        THEN ${TIFF_FOUND}   ELSE build)