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

chrome/browser/extensions/unpacked_installer.cc

Index: chrome/browser/extensions/unpacked_installer.cc
diff --git a/chrome/browser/extensions/unpacked_installer.cc b/chrome/browser/extensions/unpacked_installer.cc
index 1849630d04036d21d602d303769218472e917786..035aecff75f90f3725cf63dc15b649098c111ff5 100644
--- a/chrome/browser/extensions/unpacked_installer.cc
+++ b/chrome/browser/extensions/unpacked_installer.cc
@@ -47,23 +47,24 @@ const char kImportMissing[] = "'import' extension is not installed.";
 const char kImportNotSharedModule[] = "'import' is not a shared module.";
 
 // Manages an ExtensionInstallPrompt for a particular extension.
-class SimpleExtensionLoadPrompt : public ExtensionInstallPrompt::Delegate {
+class SimpleExtensionLoadPrompt {
  public:
   SimpleExtensionLoadPrompt(const Extension* extension,
                             Profile* profile,
                             const base::Closure& callback);
-  ~SimpleExtensionLoadPrompt() override;
 
   void ShowPrompt();
 
-  // ExtensionInstallUI::Delegate
-  void InstallUIProceed() override;
-  void InstallUIAbort(bool user_initiated) override;
-
  private:
+  ~SimpleExtensionLoadPrompt();  // Manages its own lifetime.
+
+  void OnInstallPromptDone(ExtensionInstallPrompt::Result result);
+
   scoped_ptr<ExtensionInstallPrompt> install_ui_;
   scoped_refptr<const Extension> extension_;
   base::Closure callback_;
+
+  DISALLOW_COPY_AND_ASSIGN(SimpleExtensionLoadPrompt);
 };
 
 SimpleExtensionLoadPrompt::SimpleExtensionLoadPrompt(
@@ -81,27 +82,30 @@ SimpleExtensionLoadPrompt::~SimpleExtensionLoadPrompt() {
 }
 
 void SimpleExtensionLoadPrompt::ShowPrompt() {
+  // TODO(devlin): The AutoConfirm values should work from the
+  // ExtensionInstallPrompt code, so these should be unnecessary.
   switch (extensions::ScopedTestDialogAutoConfirm::GetAutoConfirmValue()) {
     case extensions::ScopedTestDialogAutoConfirm::NONE:
+      // Unretained() is safe because this object manages its own lifetime.
       install_ui_->ShowDialog(
-          this, extension_.get(), nullptr,
+          base::Bind(&SimpleExtensionLoadPrompt::OnInstallPromptDone,
+                     base::Unretained(this)),
+          extension_.get(), nullptr,
           ExtensionInstallPrompt::GetDefaultShowDialogCallback());
       break;
     case extensions::ScopedTestDialogAutoConfirm::ACCEPT:
-      InstallUIProceed();
+      OnInstallPromptDone(ExtensionInstallPrompt::Result::ACCEPTED);
       break;
     case extensions::ScopedTestDialogAutoConfirm::CANCEL:
-      InstallUIAbort(false);
+      OnInstallPromptDone(ExtensionInstallPrompt::Result::ABORTED);
       break;
   }
 }
 
-void SimpleExtensionLoadPrompt::InstallUIProceed() {
-  callback_.Run();
-  delete this;
-}
-
-void SimpleExtensionLoadPrompt::InstallUIAbort(bool user_initiated) {
+void SimpleExtensionLoadPrompt::OnInstallPromptDone(
+    ExtensionInstallPrompt::Result result) {
+  if (result == ExtensionInstallPrompt::Result::ACCEPTED)
+    callback_.Run();
   delete this;
 }