table_test.cc: add missing 5th arg in TestArgs initializer

Summary:
Adding -W and -Wextra to CXXFLAGS provoked this failure:

	  table/table_test.cc:1854:56: error: missing initializer for member ‘rocksdb::TestArgs::format_version’ [-Werror=missing-field-initializers]
	     TestArgs args = { DB_TEST, false, 16, kNoCompression };
	                                                          ^

Add the missing, 5th value (format_version).

Test Plan:
  Run "make EXTRA_CXXFLAGS='-W -Wextra'" and see fewer errors.

Reviewers: ljin, sdong, igor.sugak, igor

Reviewed By: igor

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D33765

table/table_test.cc

@@ -1851,7 +1851,7 @@ TEST(Harness, Randomized) {
 
 TEST(Harness, RandomizedLongDB) {
   Random rnd(test::RandomSeed());
-  TestArgs args = { DB_TEST, false, 16, kNoCompression };
+  TestArgs args = { DB_TEST, false, 16, kNoCompression, 0 };
   Init(args);
   int num_entries = 100000;
   for (int e = 0; e < num_entries; e++) {