Handle Edge Browser Hover

This contribution captures the hover over edge browser and sends a mouse
move event to its listener.

contributes to eclipse-platform#1540

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

@@ -78,6 +78,9 @@ public WebViewEnvironment(ICoreWebView2Environment environment) {
 	private boolean ignoreFocus;
 	private String lastCustomText;
 
+	private CursorPosition cursorPosition = CursorPosition.OUTSIDE;
+	private Point previousCursorLocation;
+
 	static {
 		NativeClearSessions = () -> {
 			ICoreWebView2CookieManager manager = getCookieManager();
@@ -654,6 +657,7 @@ void setupBrowser(int hr, long pv) {
 	browser.addListener(SWT.FocusIn, this::browserFocusIn);
 	browser.addListener(SWT.Resize, this::browserResize);
 	browser.addListener(SWT.Move, this::browserMove);
+	handleBrowserHover();
 
 	containingEnvironment.instances().add(this);
 	// Sometimes when the shell of the browser is opened before the browser is
@@ -709,6 +713,60 @@ void browserResize(Event event) {
 	controller.put_IsVisible(true);
 }
 
+private void handleBrowserHover() {
+	browser.getDisplay().timerExec(100, () -> {
+		if (browser.isDisposed()) {
+			return;
+		}
+		if (!browser.isVisible() || !hasDisplayFocus()) {
+			handleBrowserHover();
+			return;
+		}
+
+		final Point cursorLocation = browser.getDisplay().getCursorLocation();
+		Point cursorLocationInControlCoordinate = browser.toControl(cursorLocation);
+		boolean isCursorInsideBrowser = browser.getBounds().contains(cursorLocationInControlCoordinate);
+		boolean isCursorLocationChanged = !cursorLocation.equals(previousCursorLocation);
+		previousCursorLocation = cursorLocation;
+
+		switch (cursorPosition) {
+		case INSIDE:
+			if (isCursorInsideBrowser && isCursorLocationChanged) {
+				sendMouseEvent(cursorLocationInControlCoordinate, SWT.MouseMove);
+			} else if (!isCursorInsideBrowser) {
+				cursorPosition = CursorPosition.OUTSIDE;
+				sendMouseEvent(cursorLocationInControlCoordinate, SWT.MouseExit);
+			}
+			break;
+		case OUTSIDE:
+			if (isCursorInsideBrowser) {
+				cursorPosition = CursorPosition.INSIDE;
+				sendMouseEvent(cursorLocationInControlCoordinate, SWT.MouseEnter);
+			}
+			break;
+		}
+		handleBrowserHover();
+	});
+}
+
+private enum CursorPosition {
+	INSIDE, OUTSIDE
+}
+
+private void sendMouseEvent(Point cursorLocationInControlCoordinate, int mouseEvent) {
+	Event newEvent = new Event();
+	newEvent.widget = browser;
+	Point position = cursorLocationInControlCoordinate;
+	newEvent.x = position.x;
+	newEvent.y = position.y;
+	newEvent.type = mouseEvent;
+	browser.notifyListeners(newEvent.type, newEvent);
+}
+
+private boolean hasDisplayFocus() {
+	return browser.getDisplay().getFocusControl() != null;
+}
+
 @Override
 public Object evaluate(String script) throws SWTException {
 	// Feature in WebView2. ExecuteScript works regardless of IsScriptEnabled setting.