Change WebBluetooth chooser title to "pair with"

chrome/browser/chooser_controller/chooser_controller.h

Index: chrome/browser/chooser_controller/chooser_controller.h
diff --git a/chrome/browser/chooser_controller/chooser_controller.h b/chrome/browser/chooser_controller/chooser_controller.h
index bb20a77fcbd73ef1048c57eed1c005517428dfa7..891c02ef9d7a906c97b40c3578e335c962173f05 100644
--- a/chrome/browser/chooser_controller/chooser_controller.h
+++ b/chrome/browser/chooser_controller/chooser_controller.h
@@ -5,6 +5,8 @@
 #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"
 
@@ -49,7 +51,7 @@ class ChooserController {
   };
 
   // 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;
@@ -81,6 +83,10 @@ class ChooserController {
   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;