LDBCommand::InitFromCmdLineArgs() to move from template to function wrapper
Summary:
Build failure with some compiler setting with
tools/reduce_levels_test.cc:97: undefined reference to `rocksdb::LDBCommand* rocksdb::LDBCommand::InitFromCmdLineArgs<rocksdb::LDBCommand* (*)(std::string const&, std::vector<std::string, std::allocator<std::string> > const&, std::map<std::string, std::string, std::less<std::string>, std::allocator<std::pair<std::string const, std::string> > > const&, std::vector<std::string, std::allocator<std::string> > const&)>(std::vector<std::string, std::allocator<std::string> > const&, rocksdb::Options const&, rocksdb::LDBOptions const&, std::vector<rocksdb::ColumnFamilyDescriptor, std::allocator<rocksdb::ColumnFamilyDescriptor> > const*, rocksdb::LDBCommand* (*)(std::string const&, std::vector<std::string, std::allocator<std::string> > const&, std::map<std::string, std::string, std::less<std::string>, std::allocator<std::pair<std::string const, std::string> > > const&, std::vector<std::string, std::allocator<std::string> > const&))'
Fix it by changing to function pointer instead
Test Plan: Run all existing tests
Reviewers: andrewkr, kradhakrishnan, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: adsharma, lightmark, yiwu, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D58905