CMake rewriting the tests causes Mroonga to be un-buildable
on build environments where there source directory is read
only.
In the test results, the version wasn't particularly important.
Remove the version dependence of tests.
Some fixes related to commit f838b2d799 and
Rows_log_event::do_apply_event() and Update_rows_log_event::do_exec_row()
for system-versioned tables were provided by Nikita Malyavin.
This was required by test versioning.rpl,trx_id,row.
bzip2/lz4/lzma/lzo/snappy compression is now provided via *services*
they're almost like normal services, but in include/providers/
and they're supposed to provide exactly the same interface
as original compression libraries (but not everything,
only enough of if for the code to compile).
the services are implemented via dummy functions that return
corresponding error values (LZMA_PROG_ERROR, LZO_E_INTERNAL_ERROR, etc).
the actual compression libraries are linked into corresponding
provider plugins. Providers are daemon plugins that when loaded
replace service pointers to point to actual compression functions.
That is, run-time dependency on compression libraries is now on plugins,
and the server doesn't need any compression libraries to run, but
will automatically support the compression when a plugin is loaded.
InnoDB and Mroonga use compression plugins now. RocksDB doesn't,
because it comes with standalone utility binaries that cannot
load plugins.
Fix all cmake tests (including plugin) to use
MY_CHECK_AND_SET_COMPILER_FLAG. And fix that function
to be compatible with cmake 3.0. This way flag checks
are correctly cached (even in cmake 3.0) and properly reused.
* use the same HAVE_C/CXX_ variables for compiler flag tests as the rest of
the server and tokudb - to use cached results
* plugin's name should be "mroonga" not "ha_mroonga"
* don't use set_property(TARGET plugin_name ...), it aborts cmake when a plugin
id disabled, because the target doesn't exists in that case
result: mroonga can now be disabled from cmake command line
