ts: flush stdout/stderr before and after test code run

modules/ts/include/opencv2/ts/ts_ext.hpp

@@ -24,10 +24,13 @@ extern int testThreads;
 
 #define CV__TEST_INIT \
     CV__TEST_NAMESPACE_CHECK \
+    fflush(stdout); fflush(stderr); \
     cv::ipp::setIppStatus(0); \
     cv::theRNG().state = cvtest::param_seed; \
     cv::setNumThreads(cvtest::testThreads);
-#define CV__TEST_CLEANUP ::cvtest::checkIppStatus();
+#define CV__TEST_CLEANUP \
+    fflush(stdout); fflush(stderr); \
+    ::cvtest::checkIppStatus();
 #define CV__TEST_BODY_IMPL(name) \
     { \
        CV__TRACE_APP_FUNCTION_NAME(name); \