[HBASE-11187] Fix null pointer.

Author: elliott

Summary: Fix null pointer when there are no outstanding requests.

Test Plan: mvn test -Dtest=TestEmptyMetaInfo

Reviewers: manukranthk

Reviewed By: manukranthk

Subscribers: hbase-eng@

Differential Revision: https://phabricator.fb.com/D1336725

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.89-fb@1596348 13f79535-47bb-0310-9956-ffa450edef68
[HBASE-10891] Setup Socks Proxy in HBaseRPC for HadoopRPC

Author: manukranthk

Summary: This diff attempts to setup Socks Proxy support to talk to master.

Test Plan: Test on Calypso.

Reviewers: liyintang, nileema, adela, daviddeng

Reviewed By: daviddeng

Subscribers: hbase-eng@

Differential Revision: https://phabricator.fb.com/D1295350

Tasks: 4165944

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.89-fb@1596349 13f79535-47bb-0310-9956-ffa450edef68
[HBASE-9704] Optimize tableExists in HBaseAdmin

Author: manukranthk

Summary:
The Master's tableExists function is more optimal compared to HBaseAdmin's, reverting to use the master's logic.
HBaseAdmin.tableExists previously used to take : ~25s.
Now it takes ~2s.

Test Plan: Tested on calypsohbase001-frc1 and found that it is 10X faster.

Reviewers: rshroff, aaiyer

Reviewed By: aaiyer

Subscribers: hbase-eng@

Differential Revision: https://phabricator.fb.com/D1336866

Tasks: 4253634

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.89-fb@1596350 13f79535-47bb-0310-9956-ffa450edef68
[master] Pull async and sync thrift interfaces into two different java interfaces

Author: elliott

Summary:
This pulls the async and sync interfaces apart.  This should allow client implementation to be disconnected from the server.

Currently everything on the server side uses the sync method. All things on the client side will use the thrift async methods.

Test Plan:
mvn clean test

Added unit test to make sure that all of our thrift interfaces are well defined and that sync and async change together.

Reviewers: manukranthk

Reviewed By: manukranthk

Subscribers: andrewcox, hbase-eng@

Differential Revision: https://phabricator.fb.com/D1327677

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.89-fb@1596351 13f79535-47bb-0310-9956-ffa450edef68