Extend and refactor GDataFileBase and derived classes.

Extend and refactor GDataFileBase and derived classes.

This CL makes the following changes:
1. Change GDataFile to name regular files by the 'title' attribute
   instead of the original 'filename' at the time of upload. Also,
   rename 'original_file_name' to 'title'.
2. Add GDataFileBase::SetFileNameFromTitle() to reset the file name
   of a GDataFileBase instance to its title before de-duplication.
3. Add resource ID and self link to GDataDirectory.
4. Add GDataDirectory::TakeFile() for transferring ownership of a
   GDataFileBase instance from one directory to another.

BUG=chromium-os:26962
TEST=Tested the following:
1. Run "unit_tests --gtest_filter='*GData*'"
2. Verify that the CrOS file manager shows the 'title' attribute of a
   regular file, which is consistent with the web interface as follows:
   - Upload a new file.
   - Check the file name shown in CrOS file manager and on the web.
   - Rename the uploaded file.
   - Check again the file name shown in CrOS file manager and on the web.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=126357

[Ben Chan, 2012-03-12 21:45:58]

Splitted from https://chromiumcodereview.appspot.com/9662041/ as suggested by
satorux@

https://chromiumcodereview.appspot.com/9694016/diff/1/chrome/browser/chromeos...
File chrome/browser/chromeos/gdata/gdata_files.h (right):

https://chromiumcodereview.appspot.com/9694016/diff/1/chrome/browser/chromeos...
chrome/browser/chromeos/gdata/gdata_files.h:81: // GDataDirectory::TakeFile()
needs to call GDataFileBase::set_parent().
Couldn't figure out how to only friend the set_parent method when GDataDirectory
is forward-declared, so friend the entire class here.

[Ben Chan, 2012-03-13 05:29:03]

zel / satoru:

Could you lgtm on this CL?  It is just part of the other CL:
https://chromiumcodereview.appspot.com/9662041.  Split into two CLs to make it
easier to track the changes and revert if necessary.

[satorux1, 2012-03-13 06:03:30]

looking good.

https://chromiumcodereview.appspot.com/9694016/diff/1/chrome/browser/chromeos...
File chrome/browser/chromeos/gdata/gdata_files.h (right):

https://chromiumcodereview.appspot.com/9694016/diff/1/chrome/browser/chromeos...
chrome/browser/chromeos/gdata/gdata_files.h:78: virtual void
UseOriginalFileName();
I got confused about this one. As chatted offline, confusion mainly comes from
the function name, and the fact it's hard to tell the difference between
|file_name| and |original_file_name| from the variable names alone. 

original_file_name_ is now coming from "title" field, so renaming it to |title|
would make it clearer and more accurate.

UseOriginalFileName() would be replaced by something like

// Gets the file name from |title_|.
// Note that Suffixes like "(2)" for files with duplicate names are added
// by AddFile(), not by this function.
FilePath GetFileNameFromTitle();

And the function will be used like:

file_name_ = GetFileNameFromTitle();

[Ben Chan, 2012-03-13 06:28:12]

https://chromiumcodereview.appspot.com/9694016/diff/1/chrome/browser/chromeos...
File chrome/browser/chromeos/gdata/gdata_files.h (right):

https://chromiumcodereview.appspot.com/9694016/diff/1/chrome/browser/chromeos...
chrome/browser/chromeos/gdata/gdata_files.h:78: virtual void
UseOriginalFileName();
On 2012/03/13 06:03:30, satorux1 wrote:
> I got confused about this one. As chatted offline, confusion mainly comes from
> the function name, and the fact it's hard to tell the difference between
> |file_name| and |original_file_name| from the variable names alone. 
> 
> original_file_name_ is now coming from "title" field, so renaming it to
|title|
> would make it clearer and more accurate.
> 
> UseOriginalFileName() would be replaced by something like
> 
> // Gets the file name from |title_|.
> // Note that Suffixes like "(2)" for files with duplicate names are added
> // by AddFile(), not by this function.
> FilePath GetFileNameFromTitle();
> 
> And the function will be used like:
> 
> file_name_ = GetFileNameFromTitle();

Done.

[satorux1, 2012-03-13 06:32:01]

LGTM

http://codereview.chromium.org/9694016/diff/4001/chrome/browser/chromeos/gdat...
File chrome/browser/chromeos/gdata/gdata_files.h (right):

http://codereview.chromium.org/9694016/diff/4001/chrome/browser/chromeos/gdat...
chrome/browser/chromeos/gdata/gdata_files.h:78: // de-duplication.
"name de-duplication" wasn't clear to me at first. maybe add something like

// de-duplication. See also the comment at AddFile().

[commit-bot: I haz the power, 2012-03-13 06:56:59]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/benchan@chromium.org/9694016/3003

[commit-bot: I haz the power, 2012-03-13 08:23:24]

Change committed as 126357