Merge pull request #901 from mapleFU:opt-using-move

PiperOrigin-RevId: 420662938

util/env_posix.cc

@@ -136,7 +136,7 @@ class Limiter {
 class PosixSequentialFile final : public SequentialFile {
  public:
   PosixSequentialFile(std::string filename, int fd)
-      : fd_(fd), filename_(filename) {}
+      : fd_(fd), filename_(std::move(filename)) {}
   ~PosixSequentialFile() override { close(fd_); }
 
   Status Read(size_t n, Slice* result, char* scratch) override {