BUG#978479: Wrong result (extra rows) with derived_with_keys+loosescan+semijoin=ON, materialization=OFF
Part#1: make EXPLAIN's plan match the one by actual execution: 
Item_subselect::used_tables() should return the same value irrespectively 
of whether we're running an EXPLAIN or a SELECT.

This can result in bad deadlocks (e.g loader lock), seen in latest crash reports.

since password characters can contain quotes or spaces.

The proper quoting method for command line arguments used here was  extracted from
http://blogs.msdn.com/b/twistylittlepassagesallalike/archive/2011/04/23/everyone-quotes-arguments-the-wrong-way.aspx

Additionally, mysql_install_db.exe now passes root password to "mysqld.exe --bootstrap"
 in hexadecimal form, to handle potential special chars inside password string literal.

The previous patch for the bug (that erroneously identified the bug as
bug 972973 in its comment) was incorrect. 
It turned out that the code that triggered the abort complain reported for
the bug was not needed at all.

When the function free_tmp_table deletes the handler object for
a temporary table the field TABLE::file for this table should be
set to NULL. Otherwise an assertion failure may occur.

This bug happened because the function find_field_in_view formed
autogenerated names of view columns without a possibility to roll
them back. In some situation it could cause memory misuses reported
by valgrind or even crashes.

        RB-tree index in the MEMORY table fails if it grews over 4G.
        That happened because the old_allocated variable in hp_rb_write_key()
        had the uint type. Changed with the 'size_t' type to be same as the
        'rb_tree.allocated'.

per-file comments:
  storage/heap/hp_write.c
MDEV-80 Memory engine table full at much less than max_heap_table_size with btree index.
        uint->size_t for the 'old_allocated'.

When a view/derived table is converted from merged to materialized the
items from the used_item lists are substituted for items referring to
the fields of the result of the materialization. The problem appeared
with queries employing natural joins. Since the resolution of a natural
join was performed only once the used_item list formed at the second
execution of the query lacked the references to the fields that were
used only in the equality predicates generated for the natural join.

don't cast implicitly an int to a char, when a boolean value is desired.

Fixed additional changed pbxt test cases

The main problem was a bug in CSV where it provided wrong statistics (it claimed the table was empty when it wasn't)
I also fixed wrong freeing of blob's in the CSV handler. (Any call to handler::read_first_row() on a CSV table with blobs would fail)



mysql-test/r/csv.result:
  Added new test case
mysql-test/r/partition_innodb.result:
  Updated test results after fixing bug with impossible partitions and const tables
mysql-test/t/csv.test:
  Added new test case
sql/sql_select.cc:
  Cleaned up code for handling of partitions.
  Fixed also a bug where we didn't threat a table with impossible partitions as a const table.
storage/csv/ha_tina.cc:
  Allocate blobroot onces.

- When doing join optimization, pre-sort the tables so that they mimic the execution
  order we've had with 'semijoin=off'. 
- That way, we will not get regressions when there are two query plans (the old and the
  new) that have indentical costs but different execution times (because of factors that
  the optimizer was not able to take into account).
  

Thanks to Maarten Vanraes for the patch


sql/sql_plugin.cc:
  Fix plugin boolean variables to receive the value "1", not "-1", when they are set to 1.
  Aside from being bizarre, the existing behavior is unportable: machines where char is unsigned print "255" instead.