Remove parent* arg from GDataEntry ctor.

Remove parent* arg from GDataEntry ctor.

* Remove static FromDocumentEntry from GDataEntry, GDataFile, GDataDirectory. Replace with InitFromDocumentEntry.
* Move common code from GDataFile::InitFromDocumentEntry and GDataDirectory::InitFromDocumentEntry to GDataEntry::InitFromDocumentEntry.
* Add GDataDirectoryService::FromDocumentEntry and use this everywhere.
* Make ctors of GDataFile, GDataDirectory private, so these must be created by GDataDirectoryService's CreateGDataFile and
CreateGDataDirectory. Make GDataEntry ctor protected.

BUG=141494
TEST=unit tests.
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=151008

[achuithb, 2012-08-09 23:50:17]

Please review. Thank you!

[satorux1, 2012-08-10 00:45:27]

LGTM. nice!

https://chromiumcodereview.appspot.com/10854083/diff/10002/chrome/browser/chr...
File chrome/browser/chromeos/gdata/gdata_files.cc (right):

https://chromiumcodereview.appspot.com/10854083/diff/10002/chrome/browser/chr...
chrome/browser/chromeos/gdata/gdata_files.cc:536:
entry->InitFromDocumentEntry(doc);
because InitFromDocumentEntry() is virtual,
GDataDirectory::InitFromDocumentEntry is called if |entry| was created by
CreateGDataFile() right?

[achuithb, 2012-08-10 08:42:00]

https://chromiumcodereview.appspot.com/10854083/diff/10002/chrome/browser/chr...
File chrome/browser/chromeos/gdata/gdata_files.cc (right):

https://chromiumcodereview.appspot.com/10854083/diff/10002/chrome/browser/chr...
chrome/browser/chromeos/gdata/gdata_files.cc:536:
entry->InitFromDocumentEntry(doc);
On 2012/08/10 00:45:27, satorux1 wrote:
> because InitFromDocumentEntry() is virtual,
> GDataDirectory::InitFromDocumentEntry is called if |entry| was created by
> CreateGDataFile() right?

Yup. The correct InitFromDocumentEntry is called due to dynamic/virtual
dispatch. GDataDirectory::InitFromDocumentEntry for CreateGDataDirectory and
GDataFile::InitFromDocumentEntry for CreateGDataFile.