Quite remarkably, unsettled US internet radio firm Pandora has managed to recuperate its tumbling value and engineer an all-stock sale to SiriusXM for $3.5 billion – the satellite radio giant’s second bite at the cherry. If handled correctly by John Malone’s mass media group Liberty Media, the merger has the potential to create a surprise third contender in the music streaming space. Some two and a half years ago, Pandora had a market cap of $3 billion, dropping to $2.6 billion a year later and further again to $1.8 billion the following year, prior to climbing back to $2.4 billion as of writing. There will be some happy faces among Pandora’s investors, that’s for sure. Conversely, shares in SiriusXM dipped…