Move command handling and updating off Browser and onto a helper object.

chrome/browser/ui/browser_commands.h

Index: chrome/browser/ui/browser_commands.h
===================================================================
--- chrome/browser/ui/browser_commands.h	(revision 144460)
+++ chrome/browser/ui/browser_commands.h	(working copy)
@@ -13,6 +13,7 @@
 #include "webkit/glue/window_open_disposition.h"
 
 class Browser;
+class CommandObserver;
 class GURL;
 class Profile;
 class TabContents;
@@ -24,6 +25,20 @@
 
 namespace chrome {
 
+// For all commands, where a tab is not specified, the active tab is assumed.
+
+bool IsCommandEnabled(Browser* browser, int command);
+bool SupportsCommand(Browser* browser, int command);
+bool ExecuteCommand(Browser* browser, int command);
+bool ExecuteCommandWithDisposition(Browser* browser,
+                                   int command,
+                                   WindowOpenDisposition disposition);
+void UpdateCommandEnabled(Browser* browser, int command, bool enabled);
+void AddCommandObserver(Browser*, int command, CommandObserver* observer);
+void RemoveCommandObserver(Browser*, int command, CommandObserver* observer);
+
+int GetContentRestrictions(const Browser* browser);
+
 // Opens a new window with the default blank tab.
 void NewEmptyWindow(Profile* profile);
 
@@ -39,15 +54,16 @@
 // |profile|, that session is re-used.
 void OpenURLOffTheRecord(Profile* profile, const GURL& url);
 
-bool CanGoBack(Browser* browser);
+bool CanGoBack(const Browser* browser);
 void GoBack(Browser* browser, WindowOpenDisposition disposition);
-bool CanGoForward(Browser* browser);
+bool CanGoForward(const Browser* browser);
 void GoForward(Browser* browser, WindowOpenDisposition disposition);
 bool NavigateToIndexWithDisposition(Browser* browser,
                                     int index,
                                     WindowOpenDisposition disp);
 void Reload(Browser* browser, WindowOpenDisposition disposition);
 void ReloadIgnoringCache(Browser* browser, WindowOpenDisposition disposition);
+bool CanReload(const Browser* browser);
 void Home(Browser* browser, WindowOpenDisposition disposition);
 void OpenCurrentURL(Browser* browser);
 void Stop(Browser* browser);
@@ -56,6 +72,8 @@
 void CloseWindow(Browser* browser);
 void NewTab(Browser* browser);
 void CloseTab(Browser* browser);
+void RestoreTab(Browser* browser);
+bool CanRestoreTab(const Browser* browser);
 void SelectNextTab(Browser* browser);
 void SelectPreviousTab(Browser* browser);
 void OpenTabpose(Browser* browser);  // Mac-only
@@ -64,12 +82,17 @@
 void SelectNumberedTab(Browser* browser, int index);
 void SelectLastTab(Browser* browser);
 void DuplicateTab(Browser* browser);
+bool CanDuplicateTab(const Browser* browser);
 void WriteCurrentURLToClipboard(Browser* browser);
 void ConvertPopupToTabbedBrowser(Browser* browser);
 void Exit();
 void BookmarkCurrentPage(Browser* browser);
+bool CanBookmarkCurrentPage(const Browser* browser);
+void BookmarkAllTabs(Browser* browser);
+bool CanBookmarkAllTabs(const Browser* browser);
 void PinCurrentPageToStartScreen(Browser* browser);
 void SavePage(Browser* browser);
+bool CanSavePage(const Browser* browser);
 void ShowFindBar(Browser* browser);
 void ShowPageInfo(Browser* browser,
                   content::WebContents* web_contents,
@@ -78,8 +101,11 @@
                   bool show_history);
 void ShowChromeToMobileBubble(Browser* browser);
 void Print(Browser* browser);
+bool CanPrint(const Browser* browser);
 void AdvancedPrint(Browser* browser);
+bool CanAdvancedPrint(const Browser* browser);
 void EmailPageLocation(Browser* browser);
+bool CanEmailPageLocation(const Browser* browser);
 void Cut(Browser* browser);
 void Copy(Browser* browser);
 void Paste(Browser* browser);
@@ -115,7 +141,10 @@
                 const std::string& content_state);
 
 void ViewSelectedSource(Browser* browser);
+bool CanViewSource(const Browser* browser);
 
+bool CanCreateApplicationShortcuts(const Browser* browser);
+
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_UI_BROWSER_COMMANDS_H_