Support serviceWorker.postMessage() inside service workers

Support serviceWorker.postMessage() inside service workers
https://bugs.webkit.org/show_bug.cgi?id=180328

Reviewed by Darin Adler.

LayoutTests/imported/w3c:

Rebaseline WPT test that is now passing.

* web-platform-tests/service-workers/service-worker/ServiceWorkerGlobalScope/extendable-message-event.https-expected.txt:

Source/WebCore:

Support serviceWorker.postMessage() inside service workers.

No new tests, unskipped and rebaselined existing test that is
now passing.

* workers/service/SWClientConnection.h:
* workers/service/ServiceWorker.cpp:
(WebCore::ServiceWorker::postMessage):
* workers/service/context/SWContextManager.cpp:
(WebCore::SWContextManager::postMessageToServiceWorker):
* workers/service/context/SWContextManager.h:
* workers/service/context/ServiceWorkerThread.cpp:
(WebCore::fireMessageEvent):
(WebCore::ServiceWorkerThread::postMessageToServiceWorker):
* workers/service/context/ServiceWorkerThread.h:

Source/WebKit:

Support serviceWorker.postMessage() inside service workers.

* StorageProcess/ServiceWorker/WebSWServerConnection.cpp:
(WebKit::WebSWServerConnection::postMessageToServiceWorkerFromClient):
(WebKit::WebSWServerConnection::postMessageToServiceWorkerFromServiceWorker):
* StorageProcess/ServiceWorker/WebSWServerConnection.h:
* StorageProcess/ServiceWorker/WebSWServerConnection.messages.in:
* WebProcess/Storage/WebSWClientConnection.cpp:
(WebKit::WebSWClientConnection::postMessageToServiceWorker):
* WebProcess/Storage/WebSWClientConnection.h:
* WebProcess/Storage/WebSWContextManagerConnection.cpp:
(WebKit::WebSWContextManagerConnection::postMessageToServiceWorkerFromClient):
(WebKit::WebSWContextManagerConnection::postMessageToServiceWorkerFromServiceWorker):
* WebProcess/Storage/WebSWContextManagerConnection.h:
* WebProcess/Storage/WebSWContextManagerConnection.messages.in:

LayoutTests:

Unskip WPT test that no longer times out.

* TestExpectations:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@225462 268f45cc-cd09-0410-ab3c-d52691b4dbfc