Backed out 7 changesets (bug 1522412) for xpcshell failures at test_shouldclassify.js on a CLOSED TREE.

Backed out changeset 7c998456e1fd (bug 1522412)
Backed out changeset ebb581ddf1d1 (bug 1522412)
Backed out changeset 850e1c68d978 (bug 1522412)
Backed out changeset fe288a48cecb (bug 1522412)
Backed out changeset 5399bca472b1 (bug 1522412)
Backed out changeset 91e5b339fe11 (bug 1522412)
Backed out changeset b80098d0a5c4 (bug 1522412)