Wait for CEF close event for docks

The original solution works fine when not using the Qt event loop,
however any method of waiting with the Qt event loop causes all
CEF events to go on hold too, resulting in a hang or crash.

Instead, wait for CEF to announce it's ready, then delete the widget.

panel/browser-panel-client.cpp

@@ -213,6 +213,13 @@ bool QCefBrowserClient::OnBeforePopup(CefRefPtr<CefBrowser>, CefRefPtr<CefFrame>
 	return true;
 }
 
+void QCefBrowserClient::OnBeforeClose(CefRefPtr<CefBrowser>)
+{
+	if (widget) {
+		emit widget->CloseSafely();
+	}
+}
+
 bool QCefBrowserClient::OnSetFocus(CefRefPtr<CefBrowser>, CefFocusHandler::FocusSource source)
 {
 	/* Don't steal focus when the webpage navigates. This is especially

panel/browser-panel-client.hpp

@@ -57,6 +57,8 @@ class QCefBrowserClient : public CefClient,
 				   CefRefPtr<CefClient> &client, CefBrowserSettings &settings,
 				   CefRefPtr<CefDictionaryValue> &extra_info, bool *no_javascript_access) override;
 
+	virtual void OnBeforeClose(CefRefPtr<CefBrowser> browser) override;
+
 	/* CefFocusHandler */
 	virtual bool OnSetFocus(CefRefPtr<CefBrowser> browser, CefFocusHandler::FocusSource source) override;
 

panel/browser-panel-internal.hpp

@@ -51,6 +51,7 @@ class QCefWidgetInternal : public QCefWidget {
 	virtual bool zoomPage(int direction) override;
 	virtual void executeJavaScript(const std::string &script) override;
 
+	void CloseSafely();
 	void Resize();
 
 #ifdef __linux__
@@ -61,4 +62,7 @@ class QCefWidgetInternal : public QCefWidget {
 
 public slots:
 	void Init();
+
+signals:
+	void readyToClose();
 };

panel/browser-panel.cpp

@@ -160,21 +160,24 @@ void QCefWidgetInternal::closeBrowser()
 {
 	CefRefPtr<CefBrowser> browser = cefBrowser;
 	if (!!browser) {
-		auto destroyBrowser = [](CefRefPtr<CefBrowser> cefBrowser) {
+		auto destroyBrowser = [=](CefRefPtr<CefBrowser> cefBrowser) {
 			CefRefPtr<CefClient> client = cefBrowser->GetHost()->GetClient();
 			QCefBrowserClient *bc = reinterpret_cast<QCefBrowserClient *>(client.get());
 
-			if (bc) {
-				bc->widget = nullptr;
-			}
-
 			cefBrowser->GetHost()->CloseBrowser(true);
 
 #if !defined(_WIN32) && !defined(__APPLE__) && CHROME_VERSION_BUILD >= 6533
-			while (cefBrowser && cefBrowser->IsValid()) {
-				os_sleep_ms(10);
-			}
+			QEventLoop loop;
+
+			connect(this, &QCefWidgetInternal::readyToClose, &loop, &QEventLoop::quit);
+
+			QTimer::singleShot(1000, &loop, &QEventLoop::quit);
+
+			loop.exec();
 #endif
+			if (bc) {
+				bc->widget = nullptr;
+			}
 		};
 
 		/* So you're probably wondering what's going on here.  If you
@@ -398,6 +401,11 @@ void QCefWidgetInternal::Resize()
 #endif
 }
 
+void QCefWidgetInternal::CloseSafely()
+{
+	emit readyToClose();
+}
+
 void QCefWidgetInternal::showEvent(QShowEvent *event)
 {
 	QWidget::showEvent(event);