Bug 812813 - The Downloads Panel needs to draw your attention when a download finishes. r=mak

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rename : browser/themes/gnomestripe/downloads/download-notification.png => browser/themes/gnomestripe/downloads/download-notification-start.png
rename : browser/themes/pinstripe/downloads/download-notification.png => browser/themes/pinstripe/downloads/download-notification-start.png
rename : browser/themes/winstripe/downloads/download-notification.png => browser/themes/winstripe/downloads/download-notification-start.png