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

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

Index: chrome/browser/ui/cocoa/extensions/extension_install_view_controller.mm
diff --git a/chrome/browser/ui/cocoa/extensions/extension_install_view_controller.mm b/chrome/browser/ui/cocoa/extensions/extension_install_view_controller.mm
index 58075eb18ba443c54e5151facc2d9d54548f771f..7960f53ae0aa6b2ebfb50cc53f3f685caccbeac1 100644
--- a/chrome/browser/ui/cocoa/extensions/extension_install_view_controller.mm
+++ b/chrome/browser/ui/cocoa/extensions/extension_install_view_controller.mm
@@ -225,7 +225,7 @@ bool HasAttribute(id item, CellAttributesMask attributeMask) {
 
 - (id)initWithProfile:(Profile*)profile
             navigator:(content::PageNavigator*)navigator
-             delegate:(ExtensionInstallPrompt::Delegate*)delegate
+             delegate:(ExtensionInstallViewDelegate*)delegate
                prompt:(scoped_ptr<ExtensionInstallPrompt::Prompt>)prompt {
   // We use a different XIB in the case of bundle installs, installs with
   // webstore data, or no permission warnings. These are laid out nicely for
@@ -267,15 +267,15 @@ bool HasAttribute(id item, CellAttributesMask attributeMask) {
     displayer.browser()->OpenURL(params);
   }
 
-  delegate_->InstallUIAbort(/*user_initiated=*/true);
+  delegate_->OnStoreLinkClicked();
 }
 
 - (IBAction)cancel:(id)sender {
-  delegate_->InstallUIAbort(/*user_initiated=*/true);
+  delegate_->OnCancelButtonClicked();
 }
 
 - (IBAction)ok:(id)sender {
-  delegate_->InstallUIProceed();
+  delegate_->OnOkButtonClicked();
 }
 
 - (void)awakeFromNib {