tree 68bf59e636db2ee29e6e109f44cb905f5491cbb8
parent 8c824d673769256c8dd9054f6b35818aaffd5c18
author drousso@apple.com <drousso@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1570730685 +0000
committer drousso@apple.com <drousso@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1570730685 +0000

Web Inspector: Timelines: don't call willDispatchEvent/didDispatchEvent unless there is a listener for the event
https://bugs.webkit.org/show_bug.cgi?id=202713

Reviewed by Joseph Pecoraro.

Fixes failing inspector/timeline/timeline-recording.html after r250672. This was because the
`InspectorTimelineAgent` expected a corresponding `willDispatchEvent` before it was told
about the `didDispatchEvent`, which wasn't happening since only `willDispatchEvent` would
early-return if the `DOMWindow` didn't have any event listeners for the dispatched event. By
making the `DOMWindow::dispatchEvent` itself early-return in that case, it now handles both
`willDispatchEvent` and `didDispatchEvent`, ensuring that they are always called in pairs.

* page/DOMWindow.cpp:
(WebCore::DOMWindow::dispatchEvent):

* dom/EventTarget.cpp:
(WebCore::EventTarget::innerInvokeEventListeners):
* inspector/InspectorInstrumentation.h:
(WebCore::InspectorInstrumentation::willDispatchEvent):
(WebCore::InspectorInstrumentation::didDispatchEvent):
(WebCore::InspectorInstrumentation::willDispatchEventOnWindow):
(WebCore::InspectorInstrumentation::didDispatchEventOnWindow):
* inspector/InspectorInstrumentation.cpp:
(WebCore::InspectorInstrumentation::willDispatchEventImpl):
(WebCore::InspectorInstrumentation::didDispatchEventImpl):
(WebCore::InspectorInstrumentation::willDispatchEventOnWindowImpl):
(WebCore::InspectorInstrumentation::didDispatchEventOnWindowImpl):
`InspectorInstrumentation::willDispatchEventImpl` was always called with `hasEventListeners`
as `true`, so there's no reason to keep that parameter around. Similarly, the change inside
`DOMWindow::dispatchEvent` will make it so that the same is true for
`InspectorInstrumentation::willDispatchEventOnWindowImpl` as well.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@250977 268f45cc-cd09-0410-ab3c-d52691b4dbfc