Re-factor location bar/toolbar code to get rid of the browser dependency.

chrome/browser/command_updater.h

 // Copyright (c) 2010 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_COMMAND_UPDATER_H_
 #define CHROME_BROWSER_COMMAND_UPDATER_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/hash_tables.h"
+#include "webkit/glue/window_open_disposition.h"
 
 ////////////////////////////////////////////////////////////////////////////////
 //
 // CommandUpdater class
 //
 //   This object manages the enabled state of a set of commands. Observers
 //   register to listen to changes in this state so they can update their
 //   presentation.
 //
 class CommandUpdater {
  public:
   // A Delegate object implements this interface so that it can execute commands
   // when needed.
   class CommandUpdaterDelegate {
    public:
-    // Perform the action associated with the command with the specified ID.
-    virtual void ExecuteCommand(int id) = 0;
+    // Performs the action associated with the command with the specified ID and
+    // using the given disposition.
+    virtual void ExecuteCommandWithDisposition(
+        int id,
+        WindowOpenDisposition disposition) = 0;

[sky, 2012/03/12 15:14:05]

It doesn't scale to add a new argument to this interface. Could you instead have
the reload button push the window open disposition to the LocationBar and have
reload get the disposition from the locationbar? This is similar to how
OpenCurrentURL works.

[altimofeev, 2012/03/12 15:38:42]

I'm not agree with you:
1. Having disposition as an argument is logically consistent, because Browser,
which is the only CommmandUpdaterDelegate's successor, always calls
ExecuteCommandWithDisposition.
2. No obvious reason, why this interface will need a new argument.
3. OpenCurrentURL's solution looks like a hack for me: method
GetWindowOpenDisposition doesn't look like related to LocationBar, because
WindowOpenDisposition is event's property, not UI's.
4. Furthermore, OpenCurrentURL hack only confirms, that CommandUpdater interface
should be changed.

What am I missing?

 
    protected:
     virtual ~CommandUpdaterDelegate();
   };
 
   // Create a CommandUpdater with a CommandUpdaterDelegate to handle execution
   // of specific commands.
   explicit CommandUpdater(CommandUpdaterDelegate* handler);
   virtual ~CommandUpdater();
 
   // Returns true if the specified command ID is supported.
   bool SupportsCommand(int id) const;
 
   // Returns true if the specified command ID is enabled. The command ID must be
   // supported by this updater.
   bool IsCommandEnabled(int id) const;
 
-  // Performs the action associated with this command ID.
+  // Performs the action associated with this command ID using CURRENT_TAB
+  // disposition.
   // TODO(beng): get rid of this since it's effectively just a pass-thru and the
   // call sites would be better off using more well defined delegate interfaces.
   void ExecuteCommand(int id);
 
+  // Performs the action associated with this command ID using the given
+  // disposition.
+  void ExecuteCommandWithDisposition(int id, WindowOpenDisposition disposition);
+
   // An Observer interface implemented by objects that want to be informed when
   // the state of a particular command ID is modified.
   class CommandObserver {
    public:
     // Notifies the observer that the enabled state has changed for the
     // specified command id.
     virtual void EnabledStateChangedForCommand(int id, bool enabled) = 0;
 
    protected:
     virtual ~CommandObserver();
@@ skipping 29 matching lines @@
 
   // This is a map of command IDs to states and observer lists
   typedef base::hash_map<int, Command*> CommandMap;
   CommandMap commands_;
 
   CommandUpdater();
   DISALLOW_COPY_AND_ASSIGN(CommandUpdater);
 };
 
 #endif  // CHROME_BROWSER_COMMAND_UPDATER_H_