Setup field trial for one-click signin inforbar.

chrome/browser/api/infobars/one_click_signin_infobar_delegate.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_API_INFOBARS_ONE_CLICK_SIGNIN_INFOBAR_DELEGATE_H_
+#define CHROME_BROWSER_API_INFOBARS_ONE_CLICK_SIGNIN_INFOBAR_DELEGATE_H_
+
+#include "chrome/browser/api/infobars/confirm_infobar_delegate.h"
+#include "third_party/skia/include/core/SkColor.h"
+
+// An interface derived from ConfirmInfoBarDelegate implemented for the
+// one-click sign in inforbar experiments.
+class OneClickSigninInfoBarDelegate : public ConfirmInfoBarDelegate {
+ public:
+  static const SkColor kDefaultColor;

[Peter Kasting, 2012/09/11 23:02:07]

Nit: If your intent is always to either change all the colors or none, consider
eliminating this and replacing with a boolean member of AlternateColors called
"enabled" or some such.  This is a little clearer than specifying a default and
then checking to see if the colors differ from that, especially if for some
crazy reason we wanted to use an experimental color that happened to match the
"default" value.

[Roger Tawa OOO till Jul 10th, 2012/09/12 15:07:14]

Done.

+
+  struct AlternateColors {
+    SkColor infobar_top_color;
+    SkColor infobar_bottom_color;
+    SkColor button_text_color;
+    SkColor button_background_color;
+    SkColor button_border_color;
+  };
+
+  explicit OneClickSigninInfoBarDelegate(InfoBarService* infobar_service);
+  virtual ~OneClickSigninInfoBarDelegate();
+
+  // Returns the colours to use with the one click signin infobar.  The colours
+  // depend on the experimental group.
+  virtual void GetAlternateColors(AlternateColors* alt_colors);
+
+ private:
+#if defined(OS_WIN)
+   // Because the experiment is only running on windows, only override this
+   // function on that platform.  Other platforms that support one-click sign in
+   // will create a regular confirm infobar with no support for colour changes.
+
+  // InfoBarDelegate:
+  virtual InfoBar* CreateInfoBar(InfoBarService* owner) OVERRIDE;
+#endif
+
+  DISALLOW_COPY_AND_ASSIGN(OneClickSigninInfoBarDelegate);
+};
+
+#endif  // CHROME_BROWSER_API_INFOBARS_ONE_CLICK_SIGNIN_INFOBAR_DELEGATE_H_