Change WebBluetooth chooser title to "pair with"

chrome/browser/chooser_controller/chooser_controller.h

 // Copyright 2016 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_CHOOSER_CONTROLLER_CHOOSER_CONTROLLER_H_
 #define CHROME_BROWSER_CHOOSER_CONTROLLER_CHOOSER_CONTROLLER_H_
 
+#include <utility>
+
 #include "base/macros.h"
 #include "base/strings/string16.h"
 
 namespace content {
 class RenderFrameHost;
 }
 
 // Subclass ChooserController to implement a chooser, which has some
 // introductory text and a list of options that users can pick one of.
 // Your subclass must define the set of options users can pick from;
@@ skipping 24 matching lines @@
     // options have been moved earlier by 1 slot. Calling GetOption(index)
     // from inside a call to OnOptionRemoved will NOT see the removed string
     // since the options have already been updated.
     virtual void OnOptionRemoved(size_t index) = 0;
 
    protected:
     virtual ~Observer() {}
   };
 
   // Returns the text to be displayed in the chooser title.
-  base::string16 GetTitle() const;
+  virtual base::string16 GetTitle() const = 0;
 
   // Returns the label for OK button.
   virtual base::string16 GetOkButtonLabel() const = 0;
 
   // The number of options users can pick from. For example, it can be
   // the number of USB/Bluetooth device names which are listed in the
   // chooser so that users can grant permission.
   virtual size_t NumOptions() const = 0;
 
   // The |index|th option string which is listed in the chooser.
@@ skipping 11 matching lines @@
   // closes without the user taking an explicit action.
   virtual void Close() = 0;
 
   // Open help center URL.
   virtual void OpenHelpCenterUrl() const = 0;
 
   // Only one observer may be registered at a time.
   void set_observer(Observer* observer) { observer_ = observer; }
   Observer* observer() const { return observer_; }
 
+ protected:
+  // The pair is a (chooser title prefix, URL origin(true)/otherwise(false)).
+  std::pair<base::string16, bool> GetTitlePrefix() const;
+
  private:
   content::RenderFrameHost* owning_frame_;
   Observer* observer_ = nullptr;
 
   DISALLOW_COPY_AND_ASSIGN(ChooserController);
 };
 
 #endif  // CHROME_BROWSER_CHOOSER_CONTROLLER_CHOOSER_CONTROLLER_H_