Introduce FaultInjectionTestFS to test fault File system instead of E…

…nv (#6414)

Summary:
In the current code base, we can use FaultInjectionTestEnv to simulate the env issue such as file write/read errors, which are used in most of the test. The PR facebook/rocksdb#5761 introduce the File System as a new Env API. This PR implement the FaultInjectionTestFS, which can be used to simulate when File System has issues such as IO error. user can specify any IOStatus error as input, such that FS corresponding actions will return certain error to the caller.

A set of ErrorHandlerFSTests are introduced for testing
Pull Request resolved: facebook/rocksdb#6414

Test Plan: pass make asan_check, pass error_handler_fs_test.

Differential Revision: D20252421

Pulled By: zhichao-cao

fbshipit-source-id: e922038f8ce7e6d1da329fd0bba7283c4b779a21
Signed-off-by: Changlong Chen <levisonchen@live.cn>

include/rocksdb/io_status.h

@@ -209,9 +209,7 @@ inline IOStatus& IOStatus::operator=(IOStatus&& s)
     subcode_ = std::move(s.subcode_);
     s.subcode_ = kNone;
     retryable_ = s.retryable_;
-    retryable_ = false;
     data_loss_ = s.data_loss_;
-    data_loss_ = false;
     scope_ = s.scope_;
     scope_ = kIOErrorScopeFileSystem;
     delete[] state_;