Added Client-Hints.

chrome/browser/net/client_hints.h

+// Copyright (c) 2012 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 CHROME_BROWSER_NET_CLIENT_HINTS_H_
+#define CHROME_BROWSER_NET_CLIENT_HINTS_H_
+
+#include <string>
+
+#include "base/memory/ref_counted.h"
+#include "base/values.h"
+#include "ui/gfx/rect.h"
+
+class ScreenHints {

[Ryan Sleevi, 2013/01/16 23:19:56]

This should be a struct, not a class, given that all members are public.

[bengr (incorrect), 2013/01/17 01:50:44]

Done.

+ public:
+  ScreenHints() : view_bounds(gfx::Rect(0,0)), dpr(0.0), hints_str("") {}
+  ScreenHints(int width, int height, float d, std::string s) :
+    view_bounds(gfx::Rect(width, height)), dpr(d), hints_str(s) {}
+  gfx::Rect view_bounds;
+  float dpr;

[Ryan Sleevi, 2013/01/16 23:19:56]

style: Do not abbreviate dpr like this.

[bengr (incorrect), 2013/01/17 01:50:44]

Done.

+  std::string hints_str;
+};
+
+typedef std::map<std::pair<int, int>, ScreenHints> ScreenMap;
+namespace content {
+class RenderWidgetHostViewPort;
+}

[Ryan Sleevi, 2013/01/16 23:19:56]

These typedefs should appear before any class definitions.

[bengr (incorrect), 2013/01/17 01:50:44]

Done.

+
+// ClientHints is a repository in Chrome for information used
+// to create the Client-Hints request header. For more information, see:
+// https://github.com/igrigorik/http-client-hints/blob/master/
+// draft-grigorik-http-client-hints-00.txt
+
+class ClientHints : public base::RefCountedThreadSafe<ClientHints> {
+ public:
+  static scoped_refptr<ClientHints> create();
+  ~ClientHints();

[Ryan Sleevi, 2013/01/16 23:19:56]

style: create() should be Create() - although it's entirely unclear why it's
necessary

BUG: ~ClientHints should not have a public destructor. It MUST be
private/protected and friended only to RefCountedThreadSafe<ClientHints>

[bengr (incorrect), 2013/01/17 01:50:44]

Done.

+  // Checks to see if screen information is available for the render view with
+  // the given process id and render view id.
+  bool IsScreenInfoAvailable(int process_id, int render_view_id);
+
+  // Returns client hints pertaining to screen information. The format is:
+  // "vh=xx, vw=yy, dpr=zz", where xx, yy, and zz are the viewport height,
+  // viewport width, and device pixel ratio, respectively. These values are the
+  // same as the values returned by the javascript commands:
+  // window.innerHeight, window.innerWidth, and window.devicePixelRatio.
+  // The function should be called only if IsScreenInfoAvailable() returns true.
+  std::string GetScreenInfoHints(int process_id, int render_view_id);
+
+ protected:
+  ClientHints();

[Ryan Sleevi, 2013/01/16 23:19:56]

Do you expect people to be subclassing this? You have no virtual methods, so if
you were trying to use the factory pattern via Create(), then this should be
private.

[bengr (incorrect), 2013/01/17 01:50:44]

I don't expect people to be subclassing this. Done.

On 2013/01/16 23:19:56, Ryan Sleevi wrote:

+
+ private:
+  void FetchScreenInfoOnUIThread(int process_id, int render_view_id);
+  void UpdateScreenInfo(int process_id, int render_view_id,
+                        int width, int height,

[Ryan Sleevi, 2013/01/16 23:19:56]

style: viewport_width, viewport_height ?

[bengr (incorrect), 2013/01/17 01:50:44]

Done.

+                        float dpr);

[Ryan Sleevi, 2013/01/16 23:19:56]

style: meaningful name

[bengr (incorrect), 2013/01/17 01:50:44]

Done.

+
+  ScreenMap screen_hints_;
+
+  DISALLOW_COPY_AND_ASSIGN(ClientHints);
+};
+
+#endif  // CHROME_BROWSER_NET_CLIENT_HINTS_H_