[headless] Initial skeleton of headless/public/

headless/public/web_contents.h

+// Copyright 2015 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.
+
+#ifndef HEADLESS_PUBLIC_WEB_CONTENTS_H_
+#define HEADLESS_PUBLIC_WEB_CONTENTS_H_
+
+#include "base/callback.h"
+#include "base/memory/scoped_ptr.h"
+#include "headless/public/headless_export.h"
+#include "url/gurl.h"
+
+class SkBitmap;
+
+namespace content {
+class WebContents;
+}
+
+namespace headless {
+class WebFrame;
+
+class HEADLESS_EXPORT WebContents {

[Sami, 2015/12/01 14:03:58]

Could just have a top-level comment here that says what this is and that it can
only be used on the browser main thread (so that every method doesn't need to
mention it specifically).

[altimin, 2015/12/01 15:17:29]

Done.

+ public:
+  virtual ~WebContents() {}
+
+  class Observer {

[Sami, 2015/12/01 14:03:58]

How do you set the observer? Can you have several?

+   public:
+    // Will be called on browser thread.
+    virtual void DocumentOnLoadCompletedInMainFrame() = 0;
+
+    // TODO(altimin): More OnSomething() methods will go here.
+
+   protected:
+    explicit Observer(WebContents* web_contents);
+    virtual ~Observer();
+
+   private:
+    class ObserverImpl;
+    scoped_ptr<ObserverImpl> observer_;

[Sami, 2015/12/01 14:03:58]

DISALLOW_COPY_AND_ASSIGN

[altimin, 2015/12/01 15:17:29]

Done.

+  };
+
+  // Returns main frame for web page.
+  // Should be called on browser main thread.
+  virtual scoped_ptr<WebFrame> main_frame() = 0;

[Sami, 2015/12/01 14:03:58]

I don't think we can return a scoped_ptr here. That would mean the caller takes
ownership. Also, please don't use hacker_style() names on virtual functions.

[altimin, 2015/12/01 15:17:29]

Done.

+
+  // Requests browser tab to nagivate to given url.
+  // Should be called on browser main thread.
+  virtual void OpenURL(const GURL& url) = 0;
+
+  using ScreenshotCallback = base::Callback<void(scoped_ptr<SkBitmap>)>;
+  // Requests an image of web contents.
+  // Should be called on browser main thread.
+  virtual void GetScreenshot(const ScreenshotCallback& callback) = 0;
+
+ protected:
+  virtual content::WebContents* web_contents() = 0;

[Sami, 2015/12/01 14:03:57]

Does this need to be here? I imagine the impl classes would just deal with
concrete impl types without going through the virtual base class?

[altimin, 2015/12/01 15:17:29]

This is needed for Observer (which is a wrapper around
content::WebContentsObserver, which require content::WebContents to be passed to
constructor). 

Alternatively, we can cast WebContents to WebContentsImpl in Observer, but I
wonder if it is going to be a good idea.

+};

[Sami, 2015/12/01 14:03:58]

DISALLOW_COPY_AND_ASSIGN

+
+}  // namespace headless
+
+#endif  // HEADLESS_PUBLIC_WEB_CONTENTS_H_