Merge pull request #3622 from nagua:fix_find_gstreamer

cmake/OpenCVFindLibsVideo.cmake

@@ -32,7 +32,7 @@ if(WITH_GSTREAMER AND NOT WITH_GSTREAMER_0_10)
 endif(WITH_GSTREAMER AND NOT WITH_GSTREAMER_0_10)
 
 # if gstreamer 1.x was not found, or we specified we wanted 0.10, try to find it
-if(WITH_GSTREAMER_0_10 OR NOT HAVE_GSTREAMER)
+if(WITH_GSTREAMER AND NOT HAVE_GSTREAMER OR WITH_GSTREAMER_0_10)
   CHECK_MODULE(gstreamer-base-0.10 HAVE_GSTREAMER_BASE)
   CHECK_MODULE(gstreamer-video-0.10 HAVE_GSTREAMER_VIDEO)
   CHECK_MODULE(gstreamer-app-0.10 HAVE_GSTREAMER_APP)
@@ -47,7 +47,7 @@ if(WITH_GSTREAMER_0_10 OR NOT HAVE_GSTREAMER)
       set(GSTREAMER_RIFF_VERSION ${ALIASOF_gstreamer-riff-0.10_VERSION})
       set(GSTREAMER_PBUTILS_VERSION ${ALIASOF_gstreamer-pbutils-0.10_VERSION})
   endif()
-endif(WITH_GSTREAMER_0_10 OR NOT HAVE_GSTREAMER)
+endif(WITH_GSTREAMER AND NOT HAVE_GSTREAMER OR WITH_GSTREAMER_0_10)
 
 # --- unicap ---
 ocv_clear_vars(HAVE_UNICAP)