Fixed BUG#19542 "InnoDB doesn't increase the Handler_read_prev couter".
 Fixed BUG#19609 "Case sensitivity of innodb_data_file_path gives stupid error".
 Fixed BUG#19727 "InnoDB crashed server and crashed tables are ot recoverable".
 Also:
 * Remove remnants of the obsolete concept of memoryfixing tables and indexes.
 * Remove unused dict_table_LRU_trim().
 * Remove unused 'trx' parameter from dict_table_get_on_id_low(),
   dict_table_get(), dict_table_get_and_increment_handle_count().
 * Add a normal linked list implementation.
 * Add a work queue implementation.
 * Add 'level' parameter to mutex_create() and rw_lock_create().
   Remove mutex_set_level() and rw_lock_set_level().
 * Rename SYNC_LEVEL_NONE to SYNC_LEVEL_VARYING.
 * Add support for bound ids in InnoDB's parser.
 * Define UNIV_BTR_DEBUG for enabling consistency checks of
   FIL_PAGE_NEXT and FIL_PAGE_PREV when accessing sibling
   pages of B-tree indexes.
   btr_validate_level(): Check the validity of the doubly linked
   list formed by FIL_PAGE_NEXT and FIL_PAGE_PREV.
 * Adapt InnoDB to the new tablename to filename encoding in MySQL 5.1.
   ut_print_name(), ut_print_name1(): Add parameter 'table_id' for
   distinguishing names of tables from other identifiers.
   New: innobase_convert_from_table_id(), innobase_convert_from_id(),
        innobase_convert_from_filename(), innobase_get_charset.
   dict_accept(), dict_scan_id(), dict_scan_col(), dict_scan_table_name(),
   dict_skip_word(), dict_create_foreign_constraints_low(): Add
   parameter 'cs' so that isspace() can be replaced with my_isspace(),
   whose operation depends on the connection character set.
   dict_scan_id(): Convert identifier to UTF-8.
   dict_str_starts_with_keyword(): New extern function, to replace
   dict_accept() in row_search_for_mysql().
   mysql_get_identifier_quote_char(): Replaced with innobase_print_identifier().
   ha_innobase::create(): Remove the thd->convert_strin() call. Pass the
   statement to InnoDB in the connection character set and let InnoDB
   convert the identifier to UTF-8.
 * Add max_row_size to dict_table_t.
 * btr0cur.c
   btr_copy_externally_stored_field(): Only set the 'offset' variable
   when needed.
 * buf0buf.c
   buf_page_io_complete(): Write to the error log if the page number or
   the space id o the disk do not match those in memory. Also write to
   the error log if a page was read from the doublewrite buffer. The
   doublewrite buffer should be only read by the lower-level function
   fil_io() at database startup.
 * dict0dict.c
   dict_scan_table_name(): Remove fallback to differently encoded name
   when the table is not found. The encoding is handled at a higher level.
 * ha_innodb.cc
   Increment statistic counter in ha_innobase::index_prev() (bug 19542).
   Add innobase_convert_string wrapper function and a new file
   ha_prototypes.h.
   innobase_print_identifier(): Remove TODO comment before calling
   get_quote_char_for_identifier(). That function apparently assumes
   the identifier to be encoded in UTF-8.
 * ibuf0ibuf.c|h
   ibuf_count_get(), ibuf_counts[], ibuf_count_inited(): Define these
   only #ifdef UNIV_IBUF_DEBUG. Previously, when compiled without
   UNIV_IBUF_DEBUG, invoking ibuf_count_get() would crash InnoDB.
   The function is only being called #ifdef UNIV_IBUF_DEBUG.
 * innodb.result
   Adjust the results for changes in the foreign key error messages.
 * mem0mem.c|h
   New: mem_heap_dup(), mem_heap_printf(), mem_heap_cat().
 * os0file.c
   Check the page trailers also after writing to disk. This improves
   chances of diagnosing bug 18886.
   os_file_check_page_trailers(): New function for checking that the
   two copies of the LSN stamped on the page match.
   os_aio_simulated_handle(): Call os_file_check_page_trailers()
   before and after os_file_write().
 * row0mysql.c
   Move trx_commit_for_mysql(trx) calls before calls to
   row_mysql_unlock_data_dictionary(trx) (bug 19727).
 * row0sel.c
   row_fetch_print(): Handle SQL NULL values without crashing.
   row_sel_store_mysql_rec(): Remove useless call to rec_get_nth_field
   when handling an externally stored column.
   Fetch externally stored fields when using InnoDB's internal SQL
   parser.
   Optimize BLOB selects by using prebuilt->blob_heap directly instead
   of first reading BLOB data to a temporary heap and then copying it
   to prebuilt->blob_heap.
 * srv0srv.c
   srv_master_thread(): Remove unreachable code.
 * srv0start.c
   srv_parse_data_file_paths_and_sizes(): Accept lower-case 'm' and
   'g' as abbreviations of megabyte and gigabyte (bug 19609).
   srv_parse_megabytes(): New fuction.
 * ut0dbg.c|h
   Implement InnoDB assertions (ut_a and ut_error) with abort() when
   the code is compiled with GCC 3 or later on other platforms than
   Windows or Netware. Also disable the variable ut_dbg_stop_threads
   and the function ut_dbg_stop_thread() i this case, unless
   UNIV_SYC_DEBUG is defined. This should allow the compiler to
   generate more compact code for assertions.
 * ut0list.c|h
   Add ib_list_create_heap().