'Current and recent transfers' displays only a black box on mouseover

[Philip Khor]

The black box which appears when no transfers have/are taking place looks odd. A more meaningful description, e.g. 'none' should be put in place.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: indicator-sync 12.10.5+14.04.20131125-0ubuntu1
ProcVersionSignature: Ubuntu 3.12.0-7.15-generic 3.12.4
Uname: Linux 3.12.0-7-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.12.7-0ubuntu3
Architecture: amd64
CurrentDesktop: Unity
Date: Sat Jan 4 14:33:59 2014
InstallationDate: Installed on 2013-12-30 (4 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Alpha amd64 (20131229)
SourcePackage: indicator-sync
UpgradeStatus: No upgrade log present (probably fresh install)