[Extensions] Migrate ExtensionInstallPrompt::Delegate to be a callback

chrome/browser/ui/cocoa/extensions/extension_install_view_controller.h

Index: chrome/browser/ui/cocoa/extensions/extension_install_view_controller.h
diff --git a/chrome/browser/ui/cocoa/extensions/extension_install_view_controller.h b/chrome/browser/ui/cocoa/extensions/extension_install_view_controller.h
index f88d3dc3284e9271e9414e3cddd87c5ab727dd76..e9063864de7941034c24bc6aed1da64c165b44bb 100644
--- a/chrome/browser/ui/cocoa/extensions/extension_install_view_controller.h
+++ b/chrome/browser/ui/cocoa/extensions/extension_install_view_controller.h
@@ -21,8 +21,18 @@ namespace content {
 class PageNavigator;
 }
 
+class ExtensionInstallViewDelegate {

[Devlin, 2015/12/29 00:12:52]

It was incredibly confusing to me that two different objects would conditionally
call the ExtensionInstallPrompt::Delegate methods, and this makes it much
clearer where division of control lies.  Let me know if you think differently.

+ public:
+  virtual void OnOkButtonClicked() = 0;
+  virtual void OnCancelButtonClicked() = 0;
+  virtual void OnStoreLinkClicked() = 0;
+
+ protected:
+  virtual ~ExtensionInstallViewDelegate() {}
+};
+
 // Displays the extension or bundle install prompt, and notifies the
-// ExtensionInstallPrompt::Delegate of success or failure
+// Delegate of success or failure.
 @interface ExtensionInstallViewController : NSViewController
                                            <NSOutlineViewDataSource,
                                             NSOutlineViewDelegate> {
@@ -45,7 +55,7 @@ class PageNavigator;
 
   Profile* profile_; // weak
   content::PageNavigator* navigator_;  // weak
-  ExtensionInstallPrompt::Delegate* delegate_;  // weak
+  ExtensionInstallViewDelegate* delegate_;  // weak
   scoped_ptr<ExtensionInstallPrompt::Prompt> prompt_;
 
   base::scoped_nsobject<NSArray> warnings_;
@@ -67,7 +77,7 @@ class PageNavigator;
 
 - (id)initWithProfile:(Profile*)profile
             navigator:(content::PageNavigator*)navigator
-             delegate:(ExtensionInstallPrompt::Delegate*)delegate
+             delegate:(ExtensionInstallViewDelegate*)delegate
                prompt:(scoped_ptr<ExtensionInstallPrompt::Prompt>)prompt;
 - (IBAction)storeLinkClicked:(id)sender; // Callback for "View details" link.
 - (IBAction)cancel:(id)sender;