Updated Client-Hints patch

chrome/browser/net/client_hints.h

Index: chrome/browser/net/client_hints.h
diff --git a/chrome/browser/net/client_hints.h b/chrome/browser/net/client_hints.h
new file mode 100644
index 0000000000000000000000000000000000000000..64170ad0dc4785e19756970bf84ee58e236cb3f1
--- /dev/null
+++ b/chrome/browser/net/client_hints.h
@@ -0,0 +1,52 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.

[bengr, 2013/09/11 16:32:36]

2013, and remove (c).

+// 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/weak_ptr.h"
+
+// 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

[mmenke, 2013/09/09 16:55:30]

Nit:  Put the URL in one line.  You'll get a presubmit warning about it, but go
ahead and ignore it.

+class ClientHints {
+ public:
+  // Contains information about the client device.

[bengr, 2013/09/11 16:32:36]

I believe the current thinking is that we'll only be reporting dpr, so this
struct isn't needed.

+  struct ScreenInfo {
+    int width;
+    int height;
+    float pixel_ratio;
+  };
+
+  ClientHints();
+  ~ClientHints();
+
+  void Init();
+
+  // Retrieves screen information for use on the IO thread.
+  bool RetrieveScreenInfo();
+
+  // Returns client hints pertaining to screen information. The format is:

[bengr, 2013/09/11 16:32:36]

Update comment to reflect that we are only reporting dpr.

+  // "dh=x, dw=y, dpr=z", where x, y, and z are the device screen height,
+  // screen width, and pixel ratio, respectively. These values are the
+  // same as the values returned by the JavaScript commands:
+  // screen.height, screen.width, and window.devicePixelRatio.

[bengr, 2013/09/11 16:32:36]

remove screen.height and screen.width.

+  const std::string& GetScreenInfoHints();

[mmenke, 2013/09/09 16:55:30]

nit:  "const std::string& GetScreenInfoHints() const;"

+
+ private:
+  friend class ClientHintsTest;
+
+  void UpdateScreenInfo(ScreenInfo* info);

[bengr, 2013/09/11 16:32:36]

This can be a float* device_pixel_ratio.

+
+  std::string screen_hints_;
+
+  base::WeakPtrFactory<ClientHints> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(ClientHints);
+};
+
+#endif  // CHROME_BROWSER_NET_CLIENT_HINTS_H_