Teach Page.SetContentAsync to work with tricky content (#1130)

Author: kblok

lib/PuppeteerSharp.Tests/PageTests/SetContentTests.cs

@@ -100,5 +100,12 @@ public async Task ShouldWorkFastEnough()
                 await Page.SetContentAsync("<div>yo</div>");
             }
         }
+
+        [Fact]
+        public async Task ShouldWorkWithTrickyContent()
+        {
+            await Page.SetContentAsync("<div>hello world</div>\x7F");
+            Assert.Equal("hello world", await Page.QuerySelectorAsync("div").EvaluateFunctionAsync<string>("div => div.textContent"));
+        }
     }
 }

lib/PuppeteerSharp/DOMWorld.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Text;
 using System.Threading.Tasks;
 using Newtonsoft.Json.Linq;
 using PuppeteerSharp.Helpers;
@@ -138,11 +139,11 @@ internal async Task SetContentAsync(string html, NavigationOptions options = nul
 
             // We rely upon the fact that document.open() will reset frame lifecycle with "init"
             // lifecycle event. @see https://crrev.com/608658
-            await EvaluateFunctionAsync(@"html => {
+            await EvaluateFunctionAsync(@"base64html => {
                 document.open();
-                document.write(html);
+                document.write(atob(base64html));
                 document.close();
-            }", html).ConfigureAwait(false);
+            }", Convert.ToBase64String(Encoding.UTF8.GetBytes(html))).ConfigureAwait(false);
 
             var watcher = new LifecycleWatcher(_frameManager, Frame, waitUntil, timeout);
             var watcherTask = await Task.WhenAny(