Clang compilation fixes, closes #1432

modules/flann/include/opencv2/flann/any.h

@@ -30,6 +30,12 @@ struct empty_any
 {
 };
 
+inline std::ostream& operator <<(std::ostream& out, const empty_any&)
+{
+    out << "[empty_any]";
+    return out;
+}
+
 struct base_any_policy
 {
     virtual void static_delete(void** x) = 0;

modules/flann/include/opencv2/flann/lsh_index.h

@@ -56,7 +56,7 @@ namespace cvflann
 
 struct LshIndexParams : public IndexParams
 {
-    LshIndexParams(unsigned int table_number, unsigned int key_size, unsigned int multi_probe_level)
+    LshIndexParams(unsigned int table_number = 12, unsigned int key_size = 20, unsigned int multi_probe_level = 2)
     {
         (* this)["algorithm"] = FLANN_INDEX_LSH;
         // The number of hash tables to use