Bug 910189: Part 1 - Add "restore defaults" hooks into settings. r=margaret

--HG--
rename : mobile/android/base/resources/xml/preferences_search.xml => mobile/android/base/resources/xml-v11/preferences_search.xml
Bug 910189: Part 2 - Enable removing of default engines. r=margaret
Bug 910189: Part 3 - Restore default search engines (no dialog). r=margaret
Bug 935815 - [Australis] UITour: Allow adding a button with an action to the info panel. r=MattN
Bug 949908 - There should be only one way to start/stop tracing in the debugger; r=vporof
Bug 718532 - Error console reports an error on add-ons (first) installation attempt - Couldn't find value for key: TIME_SESSION_RESTORED. r=Unfocused
Bug 941284 - First run experience r=mbrubeck

--HG--
extra : rebase_source : fa7ac4b0baf2bcb0b7ca47086c275959f4303e8d
Bug 920236 - Add a pref to display a page on first run after install/upgrade r=mbrubeck
Backed out changesets 72a80fc289f2, 30258cd308b5, and c572890f16a2 (bug 910189) for robocop orange.
Backed out changeset be2eafebfb4d (bug 935815) for mochitest-bc orange.
CLOSED TREE
Merge m-c to fx-team.
Bug 940997: Reorganize primary controls in main menu. [r=mfinkle]
Bug 940997: Support showAsAction "ifRoom" in custom menu. [r=mfinkle]
Bug 940997: Remove icons from main menu. [r=mfinkle]
Bug 938153 - Selectively display the globe favicon placeholder when favicon fetches take long enough to be noticeable. r=mfinkle
Bug 949775 - UITelemetry should drop events on the floor if telemetry is disabled. r=mfinkle
merge fx-team to mozilla-central