Bug 926928 - Pull out the code that builds the 'Recently Closed Tabs' and 'Recently Closed Windows' to a separate module. r=Gijs

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extra : rebase_source : a0bf9a5894fc8d2b2b6fb69fe390edb3cc4c4ede
Bug 896291 - 'Close other tabs' should show the confirmation dialog if the number of tabs is greater than browser.sessionstore.max_tabs_undo. r=ttaubert,MattN

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extra : rebase_source : 0e7d5bfa58f020f49e97824da9c1c00fab369357