Fire visibilityChange event on out-of-process iframes.

third_party/WebKit/Source/web/WebSharedWorkerImpl.cpp

Index: third_party/WebKit/Source/web/WebSharedWorkerImpl.cpp
diff --git a/third_party/WebKit/Source/web/WebSharedWorkerImpl.cpp b/third_party/WebKit/Source/web/WebSharedWorkerImpl.cpp
index 393851f68e14dd69a6075b459b2ac35a85e53507..d7ea58ed5d8282897654843fc8bf0950e1cad356 100644
--- a/third_party/WebKit/Source/web/WebSharedWorkerImpl.cpp
+++ b/third_party/WebKit/Source/web/WebSharedWorkerImpl.cpp
@@ -125,7 +125,7 @@ void WebSharedWorkerImpl::initializeLoader()
     // loading requests from the worker context to the rest of WebKit and Chromium
     // infrastructure.
     DCHECK(!m_webView);
-    m_webView = WebView::create(0);
+    m_webView = WebView::create(nullptr, true);
     // FIXME: http://crbug.com/363843. This needs to find a better way to
     // not create graphics layers.
     m_webView->settings()->setAcceleratedCompositingEnabled(false);