Ampach async loading crash

[Bart Cerneels]

When loading a saved playlist with Ampache tracks. Amarok tries to
play the first few tracks immediately, skips them, then fails on a
track further in the list.

The skipping is a problem as well, which can probably be avoided by
giving ampache the time to load those tracks.

amarok: BEGIN: virtual void
Amarok::OSD::engineStateChanged(Phonon::State, Phonon::State)
amarok: END__: virtual void
Amarok::OSD::engineStateChanged(Phonon::State, Phonon::State) - Took
4.7e-05s
amarok: BEGIN: void Amarok::TrayIcon::setupToolTip()
amarok: END__: void Amarok::TrayIcon::setupToolTip() - Took 7.5e-05s
amarok: BEGIN: virtual void
Amarok::PlayPauseAction::engineStateChanged(Phonon::State,
Phonon::State)
amarok:        NEWSTATE:  1 OLDSTATE:  2
amarok: END__: virtual void
Amarok::PlayPauseAction::engineStateChanged(Phonon::State,
Phonon::State) - Took 9.6e-05s
amarok: BEGIN: virtual void
StatusBar::engineStateChanged(Phonon::State, Phonon::State)
amarok: END__: virtual void
StatusBar::engineStateChanged(Phonon::State, Phonon::State) - Took
0.00017s
amarok: BEGIN: virtual void
ProgressWidget::engineStateChanged(Phonon::State, Phonon::State)
amarok: END__: virtual void
ProgressWidget::engineStateChanged(Phonon::State, Phonon::State) -
Took 5.9e-05s
amarok:      Download Job failed!

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x438d3950 (LWP 6534)]
0x00007fd51a1278cf in KIO::TransferJob::sendAsyncData (this=0x555daa0,
dataForSlave=@0x438d2560)
    at /build/buildd/kde4libs-4.2.0/kio/kio/job.cpp:1028
1028    /build/buildd/kde4libs-4.2.0/kio/kio/job.cpp: No such file or
directory.
        in /build/buildd/kde4libs-4.2.0/kio/kio/job.cpp
(gdb) bt
#0  0x00007fd51a1278cf in KIO::TransferJob::sendAsyncData
(this=0x555daa0, dataForSlave=@0x438d2560)
    at /build/buildd/kde4libs-4.2.0/kio/kio/job.cpp:1028
#1  0x00007fd51a12adbf in KIO::TransferJob::slotDataReq (this=0x555daa0)
    at /build/buildd/kde4libs-4.2.0/kio/kio/job.cpp:1088
#2  0x00007fd51a12cded in KIO::TransferJob::qt_metacall
(this=0x555daa0, _c=QMetaObject::InvokeMetaMethod,
    _id=<value optimized out>, _a=0x5a250e0)
    at /build/buildd/kde4libs-4.2.0/obj-x86_64-linux-gnu/kio/jobclasses.moc:338
#3  0x00007fd520a70da5 in QObject::event () from /usr/lib/libQtCore.so.4
#4  0x00007fd5215fbc3d in QApplicationPrivate::notify_helper () from
/usr/lib/libQtGui.so.4
#5  0x00007fd5216039ba in QApplication::notify () from /usr/lib/libQtGui.so.4
#6  0x00007fd522a203eb in KApplication::notify (this=0x7fff2b033100,
receiver=0x555daa0, event=0x5adb6c0)
    at /build/buildd/kde4libs-4.2.0/kdeui/kernel/kapplication.cpp:307
#7  0x00007fd520a61d61 in QCoreApplication::notifyInternal () from
/usr/lib/libQtCore.so.4
#8  0x00007fd520a629fa in QCoreApplicationPrivate::sendPostedEvents ()
from /usr/lib/libQtCore.so.4
#9  0x00007fd520a8a4d3 in ?? () from /usr/lib/libQtCore.so.4
#10 0x00007fd51945cd3b in g_main_context_dispatch () from
/usr/lib/libglib-2.0.so.0
#11 0x00007fd51946050d in ?? () from /usr/lib/libglib-2.0.so.0
#12 0x00007fd5194606cb in g_main_context_iteration () from
/usr/lib/libglib-2.0.so.0
#13 0x00007fd520a8a15f in QEventDispatcherGlib::processEvents () from
/usr/lib/libQtCore.so.4
#14 0x00007fd520a60682 in QEventLoop::processEvents () from
/usr/lib/libQtCore.so.4
#15 0x00007fd520a6080d in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#16 0x00007fd5210a8df7 in KJob::exec (this=0x55613f0) at
/build/buildd/kde4libs-4.2.0/kdecore/jobs/kjob.cpp:195
#17 0x00007fd506e8bf91 in AmpacheTrackForUrlWorker::run (this=0x5564030)
    at /home/cerneelb/Code/amarok/src/services/ampache/AmpacheServiceCollection.cpp:170
#18 0x00007fd51d3fa394 in ThreadWeaver::JobRunHelper::runTheJob
(this=0x438d3010, th=0x192c700, job=0x5564030)
    at /build/buildd/kde4libs-4.2.0/threadweaver/Weaver/Job.cpp:106
#19 0x00007fd51d3fa539 in ThreadWeaver::Job::execute (this=0x5564030,
th=0x192c700)
    at /build/buildd/kde4libs-4.2.0/threadweaver/Weaver/Job.cpp:135
#20 0x00007fd51d3f94bf in ThreadWeaver::ThreadRunHelper::run
(this=0x438d30b0, parent=0x1e40f90, th=0x192c700)
    at /build/buildd/kde4libs-4.2.0/threadweaver/Weaver/Thread.cpp:95
#21 0x00007fd51d3f95de in ThreadWeaver::Thread::run (this=0x192c700)
    at /build/buildd/kde4libs-4.2.0/threadweaver/Weaver/Thread.cpp:142
#22 0x00007fd520979362 in ?? () from /usr/lib/libQtCore.so.4
#23 0x00007fd51b6993ea in start_thread () from /lib/libpthread.so.0
#24 0x00007fd51fed7c6d in clone () from /lib/libc.so.6