Checking Synced folders so fast makes the client to return a KeyError

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STEPS TO REPRODUCE
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1. If your computer is already synced with Ubuntu One service, remove it using the Ubuntu One Client
2. Using the system monitor, kill all the Ubuntu One processes
2. Log-in into the Ubuntu One client
3. When a screen called "syncing the cloud with your device" appears, mark all the folders as fast as possible

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BEHAVIOUR
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- EXPECTED: Folders to be marked to be synced
- REAL: An error is returned by the client

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WORK-AROUND
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To wait three second before marking the next item

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: ubuntuone-client 4.1.92-0ubuntu1
ProcVersionSignature: Ubuntu 3.8.0-13.23-generic 3.8.3
Uname: Linux 3.8.0-13-generic x86_64
ApportVersion: 2.9.2-0ubuntu2
Architecture: amd64
Date: Sat Mar 23 19:01:55 2013
InstallationDate: Installed on 2013-03-23 (0 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Alpha amd64 (20130323)
MarkForUpload: True
PackageArchitecture: all
ProcEnviron:
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=es_ES.UTF-8
 SHELL=/bin/bash
SourcePackage: ubuntuone-client
UpgradeStatus: No upgrade log present (probably fresh install)