Add OnBackgroundError handler API.

For the API, also adding crocksdb_status_ptr_t struct, which may be later extend to allow setting a different status (since rocksdb OnBackgroundError allow overriding the background error).
Signed-off-by: Yi Wu <yiwu@pingcap.com>

Cherry-pick recent Titan changes included in https://github.com/pingcap/titan/pull/89Signed-off-by: Yi Wu <yiwu@pingcap.com>

Signed-off-by: Little-Wallace <bupt2013211450@gmail.com>

Update `ColumnFamilyOptions` to support `DoublySkipList` in memtable.

* Update titan branch to tikv-3.0 specific branch
Signed-off-by: Yi Wu <yiwu@pingcap.com>

* Adding jemalloc-nodump-allocator option for lru-cache (#328)

Adding LRUCacheOptions::set_no_dump_allocator, so we can use JemallocNoDumpAllocator of rocksdb to exclude some LRU Cache, like block cache, from core dump.

* add delete files in ranges API for titan
Signed-off-by: Connor1996 <zbk602423539@gmail.com>

Cherry-picking the following changes that fixes zlib, jemalloc and gflags dependencies, and fixes a flaky test:
```
6ead62ca 2019-07-25 yiwu@pingcap.com     Avoid build require system zlib (#303)
9246b9c5 2019-07-25 hi@breeswish.org     Skip jemalloc options on specific platform (#324)
7a8dd731 2019-07-22 yiwu@pingcap.com     Add jemalloc-sys dependency when jemalloc is enabled (#320)
6f2c6320 2019-07-23 yiwu@pingcap.com     Not compile with gflags (#322)
09b80321 2019-07-22 yiwu@pingcap.com     Fix perf context test (#321)
d67f38e2 2019-07-21 yiwu@pingcap.com     Add jemalloc feature (#319)
```

Also update rocksdb to fix compile error with gcc9:
```
7a03c83ed 2019-07-23 psergey@askmonty.org Fix MyRocks compile warnings-treated-as-errors on Fedora 30, gcc 9.1.1 (#5553)
```

Cherry-picking #315 to tikv-3.0 branch.

Signed-off-by: Yi Wu yiwu@pingcap.com

Cherry-picking changes:
c503e736 2019-07-02 yiwu@pingcap.com     Fix Titan portable build (#312)
c17648a5 2019-07-01 yiwu@pingcap.com     Fix create_cf not passinig titan specific options to titan (#311)

* Fix titan config (#306)

* Add titan read option (#309)
Signed-off-by: Connor1996 <zbk602423539@gmail.com>

Signed-off-by: Yi Wu <yiwu@pingcap.com>

Signed-off-by: siddontang <siddontang@gmail.com>

* add recycle log configuration
Signed-off-by: siddontang <siddontang@gmail.com>

* add titan blob-run-mode

* checkout latest bug fix and titan stats

* move Titan to separate repository
Signed-off-by: Yi Wu <yiwu@pingcap.com>

This is to get around borrow checker for TiKV side of changes. Other APIs also pass in structs as reference.

Adding BlockBasedTableOptions::set_block_cache so we can set shared block cache instance to different column family and different DB instance.

Also adding LRUCacheOptions and Cache structs.

Update RocksDB to include the following changes:
018aa1972 Titan: fix error message formatting (#84)
ee2f17ca8 Fix crash with memtable prefix bloom and key out of prefix extractor domain (#5190)
16ace7c47 Titan: Add snapshot related test (#80)
ee8b59301 Titan: Fix iterator fail to pass SuperVersion to underlying iterator (#79)

Signed-off-by: Yi Wu yiwu@pingcap.com

Signed-off-by: Connor1996 <zbk602423539@gmail.com>

Update .gitmodules to point to pingcap/rocksdb tikv-3.0 branch. Also update rocksdb to include the following changes:

75133b1b6 2019-03-26 yiwu@pingcap.com Fix SstFileReader not able to open ingested file (#5097)
7ca9eb754 2019-03-26 yiwu@pingcap.com Fix BlockBasedTableIterator construction missing index_key_is_full parameter
Signed-off-by: Yi Wu <yiwu@pingcap.com>

We should not rely on a specific version of rust.

We need to support encryption environment created outside.

* Support encrypted env

* Support encrypted env

* Add tests

* guard base env

* guard base env

* guard base env

* *: add wrapper for IOStatsContext

* *: format

* *: test more fields

* *: remove allocate_nanos because darwin doesn't use it

Signed-off-by: zhangjinpeng1987 <zhangjinpeng@pingcap.com>