[Smart Lock] Add a private API to show an error bubble anchored to the Smart Lock app window.

chrome/browser/ui/proximity_auth/proximity_auth_error_bubble.h

+// Copyright 2014 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_UI_PROXIMITY_AUTH_PROXIMITY_AUTH_ERROR_BUBBLE_H_
+#define CHROME_BROWSER_UI_PROXIMITY_AUTH_PROXIMITY_AUTH_ERROR_BUBBLE_H_
+
+#include "base/macros.h"
+#include "base/strings/string16.h"
+#include "url/gurl.h"
+
+namespace content {
+class WebContents;
+}
+
+namespace gfx {
+class Range;
+class Rect;
+}
+
+class ProximityAuthErrorBubble {
+ public:
+  // Shows an error bubble with the given |message|, with an arrow pointing to
+  // the |anchor_rect|. If the |link_range| is non-empty, then that range of the
+  // |message| is drawn as a link with |link_url| as the target. When the link
+  // is clicked, the target URL opens in a new tab off of the given
+  // |web_contents|.
+  static void ShowErrorBubble(const base::string16& message,
+                              const gfx::Range& link_range,
+                              const GURL& link_url,
+                              const gfx::Rect& anchor_rect,
+                              content::WebContents* web_contents);
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ProximityAuthErrorBubble);
+};
+
+#endif  // CHROME_BROWSER_UI_PROXIMITY_AUTH_PROXIMITY_AUTH_ERROR_BUBBLE_H_