JSClass::convert is no longer used after this, but to minimize the noise, it will be deleted in a separate patch. However all non-nullptr convert hook implementations must be replaced with [@@toPrimitive] methods in this patch to avoid changing the behavior.
The changes in XrayWrapper.cpp fix a pre-existing bug: when an Xray wrapper tries to emit the "Silently denied access" warning, if id is a symbol, the existing code triggers an error trying to convert it to a string for the warning message. Implementing Symbol.toPrimitive revealed this bug; the fix is straightforward.
When workers shut down we discard the event queue rather than running it to completion. Originally workers managed their event queue themselves and would simply iterate through the array of events and cancel them all. After bug 914762 this was done by setting a (thread-)global "canceling" flag and then calling NS_ProcessPendingEvents. But this neglects that a shut down request can be received while the worker is in a sync queue. In this case, calling NS_ProcessPendingEvents will process any events pending in the sync queue, which is *not* the queue we need to cancel.
The fix is, if we are in a sync queue when NotifyInternal is called, to defer clearing the queue until the top-most sync queue is destroyed and we are about to return to the regular event queue. Only then can we call NS_ProcessPendingEvents to clear out the queue. Because we can never process any events from this queue while sync queues are active, the timing of the mass cancellation is unchanged from the perspective of events in the regular queue.
When workers shut down we discard the event queue rather than running it to completion. Originally workers managed their event queue themselves and would simply iterate through the array of events and cancel them all. After bug 914762 this was done by setting a (thread-)global "canceling" flag and then calling NS_ProcessPendingEvents. But this neglects that a shut down request can be received while the worker is in a sync queue. In this case, calling NS_ProcessPendingEvents will process any events pending in the sync queue, which is *not* the queue we need to cancel.
The fix is, if we are in a sync queue when NotifyInternal is called, to defer clearing the queue until the top-most sync queue is destroyed and we are about to return to the regular event queue. Only then can we call NS_ProcessPendingEvents to clear out the queue. Because we can never process any events from this queue while sync queues are active, the timing of the mass cancellation is unchanged from the perspective of events in the regular queue.
JSClass::convert is no longer used after this, but to minimize the noise, it will be deleted in a separate patch. However all non-nullptr convert hook implementations must be replaced with [@@toPrimitive] methods in this patch to avoid changing the behavior.
The changes in XrayWrapper.cpp fix a pre-existing bug: when an Xray wrapper tries to emit the "Silently denied access" warning, if id is a symbol, the existing code triggers an error trying to convert it to a string for the warning message. Implementing Symbol.toPrimitive revealed this bug; the fix is straightforward.
This refactoring patch separates the preparation of the fetch event
object from its dispatching, so that consumers would be able to
dispatch the event asynchronously.
