Bug 993438 - Add the necessary APIs. r=billm
Bug 993438 - Infer the eventual compartment for OMT-compiled script when the script is retrieved. r=billm

Currently, the script gets put in a compartment specified when the compilation
is initiated. Later on, when we retrieve that script and try to execute it, we
won't necessarily be in the same compartment. Currently, SM just handles this
and clones the script, but it's simpler and more efficient to just create the
script in the compartment of whoever calls FinishOffThreadScript.

Note that the existing code actually has a hazard in which the call to
GetBuiltinPrototypePure returns null - it just wasn't exercised in automation
(and was triggered by onNewScript-off-main-thread.js with this patch).
Bug 993438 - Fix up the XUL prototype cache. r=smaug
Bug 993438 - Fix up the Frame Message Manager. r=smaug
Bug 993438 - Stop implicitly cloning, and assertSameCompartment. r=billm
Bug 994798 - Disable browser_frameworker.js on Linux debug for frequent timeouts.
Bug 993071 - Add optimization tier info to js profiler pseudostack entries. r=luke
Backed out changeset aac6762777be (bug 886416) for mochitest ABORTs; CLOSED TREE
Backed out changeset e8dfde56e9ca (bug 925123) for jsreftest failures; CLOSED TREE
Merge m-c to inbound on a CLOSED TREE.
Add a comment to indicate that MOZ_COUNT_CTOR/DTOR should not be used in refcounted objects

no bug, DONTBUILD, landed on a CLOSED TREE
Improve the comment about MOZ_COUNT_CTOR/DTOR, text mostly by bent

no bug, DONTBUILD, landed on a CLOSED TREE
Bug 818822: Reduce fake audio/video rates on b2g debug only to avoid overloading mochitest emulator VMs r=padenot
CLOSED TREE
Bug 990807 - Valgrind detects leak - 4 bytes and/or 32 bytes are definitely lost (direct), r=dougc
Bug 992955 - update libnestegg to upstream commit c739433; r=kinetik
Bug 858772 - Fail if the checkForUpdate request fails instead of timing out. r=fabrice
Bug 970007 - Fix incorrect colorformat when using CairoSurface. r=gal r=bas
Bug 974017 - Update vtt.js r=rillian.
This update contains the optimization for rendering cues
with large line values. It also reverts the change to clamp
parsed line values to between -1000 and 1000.
Bug 992778 - Set docshell.chromeEventHandler in child processes. r=bz
Bug 992866 - Fix assertion in JSObject::initDenseElementsUnbarriered r=sfink