Bug 207675

Flakiness dashboard: https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#tests=fast%2Fmediastream%2Fdelayed-permission-allowed.html Flakiness start from wktesthunter data: r253388 NOERROR [r253389-r253396] UNKNOWN r253397 CRASH (Expected: PASS) Sample stacktrace (same for GTK and WPE): ``` #0 g_type_check_instance_cast () at ../../Source/glib-2.58.1/gobject/gtype.c:4052 #1 0x00007f82fbdcbecf in _ZN7WebCore30WebKitMediaStreamTrackObserver21audioSamplesAvailableERNS_23MediaStreamTrackPrivateERKN3WTF9MediaTimeERKNS_17PlatformAudioDataERKNS_22AudioStreamDescriptionEm () from /home/slave/webkitgtk/gtk-linux-64-release/build/WebKitBuild/Release/lib/libwebkit2gtk-4.0.so.37 #2 0x00007f82fce797de in _ZNK7WebCore23MediaStreamTrackPrivate15forEachObserverERKN3WTF8FunctionIFvRNS0_8ObserverEEEE () from /home/slave/webkitgtk/gtk-linux-64-release/build/WebKitBuild/Release/lib/libwebkit2gtk-4.0.so.37 #3 0x00007f82fce79b00 in _ZN7WebCore23MediaStreamTrackPrivate21audioSamplesAvailableERKN3WTF9MediaTimeERKNS_17PlatformAudioDataERKNS_22AudioStreamDescriptionEm () from /home/slave/webkitgtk/gtk-linux-64-release/build/WebKitBuild/Release/lib/libwebkit2gtk-4.0.so.37 #4 0x00007f82fce7a2ce in _ZNK7WebCore19RealtimeMediaSource15forEachObserverERKN3WTF8FunctionIFvRNS0_8ObserverEEEE () from /home/slave/webkitgtk/gtk-linux-64-release/build/WebKitBuild/Release/lib/libwebkit2gtk-4.0.so.37 #5 0x00007f82fce7a7e6 in _ZN7WebCore19RealtimeMediaSource21audioSamplesAvailableERKN3WTF9MediaTimeERKNS_17PlatformAudioDataERKNS_22AudioStreamDescriptionEm () from /home/slave/webkitgtk/gtk-linux-64-release/build/WebKitBuild/Release/lib/libwebkit2gtk-4.0.so.37 #6 0x00007f82fd614da2 in _ZN7WebCore27GStreamerAudioCaptureSource17newSampleCallbackEP11_GstElementPS0_ () from /home/slave/webkitgtk/gtk-linux-64-release/build/WebKitBuild/Release/lib/libwebkit2gtk-4.0.so.37 #7 0x00007f82f203c8ee in ffi_call_unix64 () from /usr/lib/x86_64-linux-gnu/libffi.so.6 #8 0x00007f82f203c2bf in ffi_call () from /usr/lib/x86_64-linux-gnu/libffi.so.6 #9 0x00007f82f468a966 in g_cclosure_marshal_generic_va () at ../../Source/glib-2.58.1/gobject/gclosure.c:1610 #10 0x00007f82f4689f76 in _g_closure_invoke_va () at ../../Source/glib-2.58.1/gobject/gclosure.c:873 #11 0x00007f82f46a5e27 in g_signal_emit_valist () at ../../Source/glib-2.58.1/gobject/gsignal.c:3300 #12 0x00007f82f46a6452 in g_signal_emit () at ../../Source/glib-2.58.1/gobject/gsignal.c:3447 #13 0x00007f82f550db08 in gst_app_sink_render_common () at ../../Source/gst-plugins-base-1.16.1/gst-libs/gst/app/gstappsink.c:939 #14 0x00007f82f54c2ab2 in gst_base_sink_chain_unlocked () at ../../Source/gstreamer-1.16.1/libs/gst/base/gstbasesink.c:3649 #15 0x00007f82f54c3b50 in gst_base_sink_chain_main () at ../../Source/gstreamer-1.16.1/libs/gst/base/gstbasesink.c:3775 #16 0x00007f82f53cc692 in gst_pad_chain_data_unchecked () at ../../Source/gstreamer-1.16.1/gst/gstpad.c:4327 #17 gst_pad_push_data () at ../../Source/gstreamer-1.16.1/gst/gstpad.c:4583 #18 0x00007f82f53d2e82 in gst_pad_push () at ../../Source/gstreamer-1.16.1/gst/gstpad.c:4702 #19 0x00007f82a077fe45 in gst_queue_push_one () at ../../Source/gstreamer-1.16.1/plugins/elements/gstqueue.c:1384 #20 gst_queue_loop () at ../../Source/gstreamer-1.16.1/plugins/elements/gstqueue.c:1537 #21 0x00007f82f53ffdd1 in gst_task_func () at ../../Source/gstreamer-1.16.1/gst/gsttask.c:328 #22 0x00007f82f45d16a3 in g_thread_pool_thread_proxy () at ../../Source/glib-2.58.1/glib/gthreadpool.c:307 #23 0x00007f82f45d0d45 in g_thread_proxy () at ../../Source/glib-2.58.1/glib/gthread.c:784 #24 0x00007f82f62ecfa3 in start_thread (arg=<optimized out>) at pthread_create.c:486 #25 0x00007f82f2e194cf in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95 ```