Replace "DEPRECATED" comment to "not supported"

Summary:
"DEPRECATED" is ambiguous. Make it clear that those options not supported won't take effect.
Closes https://github.com/facebook/rocksdb/pull/1995

Differential Revision: D4724241

Pulled By: siying

fbshipit-source-id: 1e812b8

include/rocksdb/advanced_options.h

@@ -529,13 +529,13 @@ struct AdvancedColumnFamilyOptions {
   // Create ColumnFamilyOptions from Options
   explicit AdvancedColumnFamilyOptions(const Options& options);
 
-  // ---------------- DEPRECATED OPTIONS ----------------
+  // ---------------- OPTIONS NOT SUPPORTED ANYMORE ----------------
 
-  // DEPRECATED
+  // NOT SUPPORTED ANYMORE
   // This does not do anything anymore.
   int max_mem_compaction_level;
 
-  // DEPRECATED -- this options is no longer used
+  // NOT SUPPORTED ANYMORE -- this options is no longer used
   // Puts are delayed to options.delayed_write_rate when any level has a
   // compaction score that exceeds soft_rate_limit. This is ignored when == 0.0.
   //
@@ -544,13 +544,13 @@ struct AdvancedColumnFamilyOptions {
   // Dynamically changeable through SetOptions() API
   double soft_rate_limit = 0.0;
 
-  // DEPRECATED -- this options is no longer used
+  // NOT SUPPORTED ANYMORE -- this options is no longer used
   double hard_rate_limit = 0.0;
 
-  // DEPRECATED -- this options is no longer used
+  // NOT SUPPORTED ANYMORE -- this options is no longer used
   unsigned int rate_limit_delay_max_milliseconds = 100;
 
-  // DEPREACTED
+  // NOT SUPPORTED ANYMORE
   // Does not have any effect.
   bool purge_redundant_kvs_while_flush = true;
 };

include/rocksdb/options.h

@@ -539,7 +539,7 @@ struct DBOptions {
   // Number of shards used for table cache.
   int table_cache_numshardbits = 6;
 
-  // DEPRECATED
+  // NOT SUPPORTED ANYMORE
   // int table_cache_remove_scan_count_limit;
 
   // The following two fields affect how archived logs will be deleted.
@@ -595,7 +595,7 @@ struct DBOptions {
   // Disable child process inherit open files. Default: true
   bool is_fd_close_on_exec = true;
 
-  // DEPRECATED -- this options is no longer used
+  // NOT SUPPORTED ANYMORE -- this options is no longer used
   bool skip_log_error_on_recovery = false;
 
   // if not zero, dump rocksdb.stats to LOG every stats_dump_period_sec
@@ -911,7 +911,7 @@ struct ReadOptions {
   // If this option is set and memtable implementation allows, Seek
   // might only return keys with the same prefix as the seek-key
   //
-  // ! DEPRECATED: prefix_seek is on by default when prefix_extractor
+  // ! NOT SUPPORTED ANYMORE: prefix_seek is on by default when prefix_extractor
   // is configured
   // bool prefix_seek;
 
@@ -922,21 +922,6 @@ struct ReadOptions {
   // Default: nullptr
   const Snapshot* snapshot;
 
-  // If "prefix" is non-nullptr, and ReadOptions is being passed to
-  // db.NewIterator, only return results when the key begins with this
-  // prefix.  This field is ignored by other calls (e.g., Get).
-  // Options.prefix_extractor must also be set, and
-  // prefix_extractor.InRange(prefix) must be true.  The iterator
-  // returned by NewIterator when this option is set will behave just
-  // as if the underlying store did not contain any non-matching keys,
-  // with two exceptions.  Seek() only accepts keys starting with the
-  // prefix, and SeekToLast() is not supported.  prefix filter with this
-  // option will sometimes reduce the number of read IOPs.
-  // Default: nullptr
-  //
-  // ! DEPRECATED
-  // const Slice* prefix;
-
   // "iterate_upper_bound" defines the extent upto which the forward iterator
   // can returns entries. Once the bound is reached, Valid() will be false.
   // "iterate_upper_bound" is exclusive ie the bound value is