fixed invalid TS call and added test files (#6495)

e581013e3d broke TS generation - please don't use "replace" to refactor function names :)

flatbuffers.pc

@@ -0,0 +1,9 @@
+libdir=/usr/local/lib
+includedir=/usr/local/include
+
+Name: FlatBuffers
+Description: Memory Efficient Serialization Library
+Version: 1.12.0
+
+Libs: -L${libdir} -lflatbuffers
+Cflags: -I${includedir}