headless: Require the user to pass in an initial URL

headless/app/headless_shell.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/location.h"
@@ skipping 19 matching lines @@
 class HeadlessShell : public HeadlessWebContents::Observer {
  public:
   HeadlessShell() : browser_(nullptr) {}
   ~HeadlessShell() override {
     if (web_contents_)
       web_contents_->RemoveObserver(this);
   }
 
   void OnStart(HeadlessBrowser* browser) {
     browser_ = browser;
-    web_contents_ = browser->CreateWebContents(gfx::Size(800, 600));
-    web_contents_->AddObserver(this);
 
     base::CommandLine::StringVector args =
         base::CommandLine::ForCurrentProcess()->GetArgs();
 
     const char kDefaultUrl[] = "about:blank";
     GURL url;
     if (args.empty() || args[0].empty()) {
       url = GURL(kDefaultUrl);
     } else {
       url = GURL(args[0]);
     }
-    if (!web_contents_->OpenURL(url)) {
+    web_contents_ = browser->CreateWebContents(url, gfx::Size(800, 600));
+    if (!web_contents_) {
       LOG(ERROR) << "Navigation failed";
-      web_contents_ = nullptr;
       browser_->Shutdown();
+      return;
     }
+    web_contents_->AddObserver(this);
   }
 
   void ShutdownIfNeeded() {
     const base::CommandLine& command_line =
         *base::CommandLine::ForCurrentProcess();
     if (!command_line.HasSwitch(switches::kRemoteDebuggingPort)) {
       web_contents_ = nullptr;
       browser_->Shutdown();
     }
   }
 
   // HeadlessWebContents::Observer implementation:
   void DocumentOnLoadCompletedInMainFrame() override {
     ShutdownIfNeeded();
   }
 
-  void DidFinishNavigation(bool success) override {}
-
  private:
   HeadlessBrowser* browser_;  // Not owned.
   std::unique_ptr<HeadlessWebContents> web_contents_;
 
   DISALLOW_COPY_AND_ASSIGN(HeadlessShell);
 };
 
 int main(int argc, const char** argv) {
   HeadlessShell shell;
   HeadlessBrowser::Options::Builder builder(argc, argv);
@@ skipping 24 matching lines @@
       LOG(ERROR) << "Malformed proxy server url";
       return EXIT_FAILURE;
     }
     builder.SetProxyServer(parsed_proxy_server);
   }
 
   return HeadlessBrowserMain(
       builder.Build(),
       base::Bind(&HeadlessShell::OnStart, base::Unretained(&shell)));
 }