This was a complex change requiring three new functions:
file_merge_files_from_draft_area_into_filearea - To just add files from a draft area into a real one (just adding or updating, not deleting)
file_merge_draft_area_into_draft_area - To merge files from two draft areas, used by the latest for creating a draft area with all the original files plus the new ones.
file_overwrite_existing_draftfile - Required to update existing files not losing metadata or references.
The whole process is the following:
User uploads a file (upload.php)
Client gets a new draftid A containing the file only (return of upload.php)
Client requests to merge that draftid in the user's private files (core_user_add_user_private_files)
Server prepares a new UNUSED draftid B from existing area
Server merges A into B
Server saves the draft B into the final area
While strictly we should not be testing private APIs, in order
to get this backported to stables without changing visibility
we use reflection to access to such private properties and methods.
Also added one exttest to verify user agent is properly sent.
Finally, fix some wrong whitespace and changed the helper class name
to better alternative.
1. Added tracker issue number in comment
2. Fixed stored_file::delete_reference()
3. repository::send_file() will throw exception if not implemented by subclass
4. Fixed renaming unit test, added one unit test for deleting original file
5. Fixed copyright statement for googledoc and picasa repository plugin
6. Implemented stored_file::set_filesize()
Includes:
* constants refactoring
* reworked db table init
* support for $CFG->debug = -1
* functional DB tests
* fixed $DB->get_indexes() to not throw exceptions when table does not exist
* fix handling of user passwords in test db
* add debug info to exception messages
* removed unnecessary PHP debug errors from mathslib
* fixed @error suppression in get_string
* fixed PHPUnit error handler setup
* added timezone info to default install
