fix tests that were relying on @@have_partitioning

sql/sql_partition_admin.cc:
  compilation failures w/o partitioning

mysql-test/include/have_partition.inc

--- require r/have_partition.require
-disable_query_log;
-show variables like 'have_partitioning';
-enable_query_log;
+if (`SELECT COUNT(*) = 0 FROM INFORMATION_SCHEMA.PLUGINS WHERE PLUGIN_NAME = 'partition' AND PLUGIN_STATUS='ACTIVE'`)
+{
+  --skip Test requires partitioning
+}

mysql-test/include/have_partition.opt

---enable-partition
+--loose-enable-partition

mysql-test/r/disabled_partition.require

-Variable_name	Value
-have_partitioning	DISABLED

mysql-test/r/have_partition.require

-Variable_name	Value
-have_partitioning	YES

mysql-test/r/not_partition.require

-Variable_name	Value
-have_partitioning	NO

mysql-test/r/not_partition.result

@@ -50,7 +50,7 @@ ERROR HY000: The 'partitioning' feature is disabled; you need MariaDB built with
 ALTER TABLE t1 PARTITION BY KEY(joined) PARTITIONS 2;
 ERROR HY000: The 'partitioning' feature is disabled; you need MariaDB built with '--with-plugin-partition' to have it working
 drop table t1;
-ERROR 42S02: Unknown table 't1'
+ERROR 42S02: Unknown table 'test.t1'
 CREATE TABLE t1 (
 firstname VARCHAR(25) NOT NULL,
 lastname VARCHAR(25) NOT NULL,
@@ -67,7 +67,7 @@ PARTITION p4 VALUES LESS THAN MAXVALUE
 );
 ERROR HY000: The 'partitioning' feature is disabled; you need MariaDB built with '--with-plugin-partition' to have it working
 drop table t1;
-ERROR 42S02: Unknown table 't1'
+ERROR 42S02: Unknown table 'test.t1'
 CREATE TABLE t1 (id INT, purchased DATE)
 PARTITION BY RANGE( YEAR(purchased) )
 SUBPARTITION BY HASH( TO_DAYS(purchased) )
@@ -78,7 +78,7 @@ PARTITION p2 VALUES LESS THAN MAXVALUE
 );
 ERROR HY000: The 'partitioning' feature is disabled; you need MariaDB built with '--with-plugin-partition' to have it working
 drop table t1;
-ERROR 42S02: Unknown table 't1'
+ERROR 42S02: Unknown table 'test.t1'
 create table t1 (a varchar(10) charset latin1 collate latin1_bin);
 insert into t1 values (''),(' '),('a'),('a '),('a  ');
 explain partitions select * from t1 where a='a ' OR a='a';

mysql-test/suite/sys_vars/r/have_partitioning_basic.result

-'#---------------------BS_STVARS_014_01----------------------#'
-SELECT COUNT(@@GLOBAL.have_partitioning);
-COUNT(@@GLOBAL.have_partitioning)
-1
-1 Expected
-'#---------------------BS_STVARS_014_02----------------------#'
-SET @@GLOBAL.have_partitioning=1;
-ERROR HY000: Variable 'have_partitioning' is a read only variable
-Expected error 'Read only variable'
-SELECT COUNT(@@GLOBAL.have_partitioning);
-COUNT(@@GLOBAL.have_partitioning)
-1
-1 Expected
-'#---------------------BS_STVARS_014_03----------------------#'
-SELECT @@GLOBAL.have_partitioning = VARIABLE_VALUE
-FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES
-WHERE VARIABLE_NAME='have_partitioning';
-@@GLOBAL.have_partitioning = VARIABLE_VALUE
-1
-1 Expected
-SELECT COUNT(@@GLOBAL.have_partitioning);
-COUNT(@@GLOBAL.have_partitioning)
-1
-1 Expected
-SELECT COUNT(VARIABLE_VALUE)
-FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES 
-WHERE VARIABLE_NAME='have_partitioning';
-COUNT(VARIABLE_VALUE)
-1
-1 Expected
-'#---------------------BS_STVARS_014_04----------------------#'
-SELECT @@have_partitioning = @@GLOBAL.have_partitioning;
-@@have_partitioning = @@GLOBAL.have_partitioning
-1
-1 Expected
-'#---------------------BS_STVARS_014_05----------------------#'
-SELECT COUNT(@@have_partitioning);
-COUNT(@@have_partitioning)
-1
-1 Expected
-SELECT COUNT(@@local.have_partitioning);
-ERROR HY000: Variable 'have_partitioning' is a GLOBAL variable
-Expected error 'Variable is a GLOBAL variable'
-SELECT COUNT(@@SESSION.have_partitioning);
-ERROR HY000: Variable 'have_partitioning' is a GLOBAL variable
-Expected error 'Variable is a GLOBAL variable'
-SELECT COUNT(@@GLOBAL.have_partitioning);
-COUNT(@@GLOBAL.have_partitioning)
-1
-1 Expected
-SELECT have_partitioning = @@SESSION.have_partitioning;
-ERROR 42S22: Unknown column 'have_partitioning' in 'field list'
-Expected error 'Readonly variable'

mysql-test/t/not_partition.test

@@ -2,10 +2,10 @@
 # Run this test only when mysqld doesn't have partitioning (not compiled with)
 # the statements are not expected to work, just check that we
 # can't crash the server
--- require r/not_partition.require
-disable_query_log;
-show variables like "have_partitioning";
-enable_query_log;
+if (`SELECT COUNT(*) = 1 FROM INFORMATION_SCHEMA.PLUGINS WHERE PLUGIN_NAME = 'partition'`)
+{
+  --skip Test requires no partitioning
+}
 --disable_warnings
 DROP TABLE IF EXISTS t1;
 --enable_warnings

mysql-test/t/partition_disabled.test

@@ -2,10 +2,10 @@
 # Run this test only when mysqld has partitioning, but it is disabled.
 # The statements are not expected to work, just check that we
 # can't crash the server.
---require r/disabled_partition.require
---disable_query_log
-show variables like "have_partitioning";
---enable_query_log
+if (`SELECT COUNT(*) = 0 FROM INFORMATION_SCHEMA.PLUGINS WHERE PLUGIN_NAME = 'partition' AND PLUGIN_STATUS='DISABLED'`)
+{
+  --skip Test requires disabled partitioning
+}
 --disable_warnings
 DROP TABLE IF EXISTS t1;
 --enable_warnings

sql/sql_partition_admin.cc

@@ -32,9 +32,9 @@
 
 #ifndef WITH_PARTITION_STORAGE_ENGINE
 
-bool Partition_statement_unsupported::execute(THD *)
+bool Sql_cmd_partition_unsupported::execute(THD *)
 {
-  DBUG_ENTER("Partition_statement_unsupported::execute");
+  DBUG_ENTER("Sql_cmd_partition_unsupported::execute");
   /* error, partitioning support not compiled in... */
   my_error(ER_FEATURE_DISABLED, MYF(0), "partitioning",
            "--with-plugin-partition");