DFG prediction propagation should agree with fixup phase over the return type of GetByVal
https://bugs.webkit.org/show_bug.cgi?id=133134

Reviewed by Mark Hahnenberg.
        
Make prediction propagator use ArrayMode refinement to decide the return type.
        
Also introduce a heap prediction intrinsic that allows us to test weird corner cases
like this. The only way we'll see a mismatch like this in the real world is probably
through a gnarly race condition.

* dfg/DFGByteCodeParser.cpp:
(JSC::DFG::ByteCodeParser::handleIntrinsic):
* dfg/DFGNode.h:
(JSC::DFG::Node::setHeapPrediction):
* dfg/DFGPredictionPropagationPhase.cpp:
(JSC::DFG::PredictionPropagationPhase::propagate):
* jsc.cpp:
(GlobalObject::finishCreation):
(functionFalse1):
(functionFalse2):
(functionUndefined1):
(functionUndefined2):
(functionFalse): Deleted.
(functionOtherFalse): Deleted.
(functionUndefined): Deleted.
* runtime/Intrinsic.h:
* tests/stress/get-by-val-double-predicted-int.js: Added.
(foo):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@169145 268f45cc-cd09-0410-ab3c-d52691b4dbfc
[Mac] DataCues do not work properly when rewinding video
https://bugs.webkit.org/show_bug.cgi?id=133138
<rdar://problem/16979086>

Reviewed by Eric Carlson.

Make the TrackPrivateBase responsible for knowing if a type of track needs a non-zero
startTimeVariance value.

Also, correct a bug in the equality test for DataCue objects.

* html/track/DataCue.cpp:
(WebCore::DataCue::isEqual): Handle the JSValue data types consistently, so that we don't attempt
to compare a JSNull against a default JSValue object.
* html/track/InbandTextTrack.cpp:
(WebCore::InbandTextTrack::startTimeVariance): Added.
* html/track/InbandTextTrack.h:
* html/track/TextTrack.cpp:
(WebCore::TextTrack::hasCue): Use new startTimeVariance method location.
* html/track/TextTrack.h:
(WebCore::TextTrack::startTimeVariance): Added.
* html/track/TextTrackCue.cpp:
(WebCore::TextTrackCue::hasEquivalentStartTime): Use new startTimeVariance location.
* html/track/TextTrackCue.h:
(WebCore::TextTrackCue::startTimeVariance): Deleted.
* html/track/TextTrackCueGeneric.h:
* platform/graphics/TrackPrivateBase.h:
(WebCore::TrackPrivateBase::startTimeVariance): Added.
* platform/graphics/avfoundation/InbandTextTrackPrivateAVF.h:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@169146 268f45cc-cd09-0410-ab3c-d52691b4dbfc