Bug 1082444 - Handle additional events when FxA EntrySheet is displayed. r=ferjm

  * Specifically, listen for 'home', 'holdhome', and 'activityrequesting', and
    when those are caught, if the EntrySheet is open, close it.
  * Also, don't try to open the EntrySheet if navigator.onLine is false; show
    an error message instead.
Bug 1073806 - In Gaia, bypass system-resize in LayoutManager in window resize event if Keyboard is showing and we've just changed orientation

Conflicts:
	apps/system/js/layout_manager.js
	apps/system/test/unit/layout_manager_test.js
Bug 1044484 - Add an external tag to gaiatest manifests to denote tests use of external internet resources
Merge pull request #26714 from zacc/bug_1044484_v2.0

Bug 1044484 - Add an external tag to gaiatest manifests to denote tests ...
Merge pull request #26707 from mnjul/bug_1073806_v2.0

Bug 1073806 - In Gaia, bypass system-resize in LayoutManager in window resize event if Keyboard is showing and we've just changed orientation
Bug 1059224 - Update launch method with manifest_url option. r=dhunt r=bsilverberg a=test-only
Bump gaiatest-v2.0 version to 0.4. a=test-only
Merge branch 'v2.0' into v2.0m

Conflicts:
	apps/system/js/layout_manager.js