Bug 958809 - Don't put broadcasted data into the regular TabStateCache r=yoric

From c4c69269516391beb36f362d76f3e440bb8cd50b Mon Sep 17 00:00:00 2001
Bug 942340 - Extracting many Telemetry statistics from sessionstore.js;r=ttaubert,froydnj
Bug 947212 - Broadcast form data and move it out of tabData.entries[] r=yoric
Bug 947212 - Tests for broadcasting form data