DevTools - now shown as popup (visible in taskbar).

- Pass null for CefWindowInfo.SetAsPopup parent handle
- Add optional params to IWebBrowser/IBrowser.ShowDevTools extension methods.

Anyone wishing to use the old behaviour can do something like

var host = browser.GetBrowserHost();

var windowInfo = new WindowInfo();
windowInfo.SetAsPopup(host.GetWindowHandle(), "DevTools");

browser.ShowDevTools(windowInfo);

Resolves #2997

Author: amaitland

CefSharp.Core/Internals/CefBrowserHostWrapper.cpp

@@ -159,7 +159,7 @@ void CefBrowserHostWrapper::ShowDevTools(IWindowInfo^ windowInfo, int inspectEle
 
     if (windowInfo == nullptr)
     {
-        nativeWindowInfo.SetAsPopup(_browserHost->GetWindowHandle(), "DevTools");
+        nativeWindowInfo.SetAsPopup(NULL, "DevTools");
     }
     else
     {

CefSharp/WebBrowserExtensions.cs

@@ -760,23 +760,29 @@ public static Task<bool> PrintToPdfAsync(this IWebBrowser browser, string path,
         /// Open developer tools in its own window. 
         /// </summary>
         /// <param name="cefBrowser">The ChromiumWebBrowser instance this method extends</param>
-        public static void ShowDevTools(this IBrowser cefBrowser)
+        /// <param name="windowInfo">window info used for showing dev tools</param>
+        /// <param name="inspectElementAtX">x coordinate (used for inspectElement)</param>
+        /// <param name="inspectElementAtY">y coordinate (used for inspectElement)</param>
+        public static void ShowDevTools(this IBrowser cefBrowser, IWindowInfo windowInfo = null, int inspectElementAtX = 0, int inspectElementAtY = 0)
         {
             var host = cefBrowser.GetHost();
             ThrowExceptionIfBrowserHostNull(host);
 
-            host.ShowDevTools();
+            host.ShowDevTools(windowInfo, inspectElementAtX, inspectElementAtY);
         }
 
         /// <summary>
         /// Open developer tools in its own window. 
         /// </summary>
         /// <param name="browser">The ChromiumWebBrowser instance this method extends</param>
-        public static void ShowDevTools(this IWebBrowser browser)
+        /// <param name="windowInfo">window info used for showing dev tools</param>
+        /// <param name="inspectElementAtX">x coordinate (used for inspectElement)</param>
+        /// <param name="inspectElementAtY">y coordinate (used for inspectElement)</param>
+        public static void ShowDevTools(this IWebBrowser browser, IWindowInfo windowInfo = null, int inspectElementAtX = 0, int inspectElementAtY = 0)
         {
             var cefBrowser = browser.GetBrowser();
             cefBrowser.ThrowExceptionIfBrowserNull();
-            cefBrowser.ShowDevTools();
+            cefBrowser.ShowDevTools(windowInfo, inspectElementAtX, inspectElementAtY);
         }
 
         /// <summary>