Bug 976967 - sdk/system module issue: the system.architecture and system.compiler return an invalid value
bug 980468: Ensure that content script syntax errors can be caught.
Bug 991692 - "TypeError: internals.tracker is undefined" found in green jetpack test runs
Merge pull request #1439 from bgabrhelik/master

Bug 976967 - sdk/system module issue: architecture and compiler return invalid values, r=@zombie
Merge pull request #1453 from erikvold/991692

Fix Bug 991692 - "TypeError: internals.tracker is undefined" found in green jetpack test runs, r=@jsantell
Merge pull request #1449 from als123/bug_980468

Bug 980468 - Ensure that content script syntax errors can be caught, r=@zombie