Backed out changeset 9511f53e3f38 (bug 934367) for frequent OSX m-oth crashes.

dom/devicestorage/test/mochitest.ini

dom/devicestorage/test/test_fs_app_permissions.html

dom/devicestorage/test/test_fs_createFile.html

dom/filesystem/CreateFileTask.cpp

dom/filesystem/CreateFileTask.h

dom/filesystem/Directory.cpp

dom/filesystem/Directory.h

dom/filesystem/FileSystemRequestParent.cpp

dom/filesystem/moz.build

dom/ipc/PContent.ipdl

dom/webidl/Directory.webidl