Fix Edge::getWebViewWrapper deadlock threat #1466

This commit makes sure while calling Edge::getWebViewWrapper with
waitForPendingWebviewTasksToFinish set to true that the method also checks for the
completion of the webViewWrapperFuture before calling a join() on it,
which can some time lead to deadlock as we allow forced execptional
completion of lastWebViewTask on timeout.

contributes to #1466

Author: amartya4256

bundles/org.eclipse.swt/Eclipse SWT Browser/win32/org/eclipse/swt/browser/Edge.java

@@ -405,13 +405,14 @@ private ICoreWebView2_13 initializeWebView_13(ICoreWebView2 webView) {
 	}
 
 	private WebViewWrapper getWebViewWrapper(boolean waitForPendingWebviewTasksToFinish) {
+		WebViewWrapper webViewWrapper = getWebViewWrapper();
 		if(waitForPendingWebviewTasksToFinish) {
 			processOSMessagesUntil(lastWebViewTask::isDone, exception -> {
 				lastWebViewTask.completeExceptionally(exception);
 				throw exception;
 			}, browser.getDisplay());
 		}
-		return webViewWrapperFuture.join();
+		return webViewWrapper;
 	}
 
 	private WebViewWrapper getWebViewWrapper() {