[Extensions] Introduce a ScopedExtensionDialogAutoConfirm

chrome/browser/extensions/webstore_installer_test.cc

Index: chrome/browser/extensions/webstore_installer_test.cc
diff --git a/chrome/browser/extensions/webstore_installer_test.cc b/chrome/browser/extensions/webstore_installer_test.cc
index cb3b7905a405bb87fadce07cb515683b10c768bb..73192e0c42f7f65f9d9995b0c0d560c65782eb9f 100644
--- a/chrome/browser/extensions/webstore_installer_test.cc
+++ b/chrome/browser/extensions/webstore_installer_test.cc
@@ -138,11 +138,13 @@ void WebstoreInstallerTest::RunTestAsync(
 }
 
 void WebstoreInstallerTest::AutoAcceptInstall() {
-  ExtensionInstallPrompt::g_auto_confirm_for_tests =
-      ExtensionInstallPrompt::ACCEPT;
+  install_auto_confirm_.reset();  // Destroy any old override first.
+  install_auto_confirm_.reset(new extensions::ScopedTestDialogAutoConfirm(
+      extensions::ScopedTestDialogAutoConfirm::ACCEPT));
 }
 
 void WebstoreInstallerTest::AutoCancelInstall() {
-  ExtensionInstallPrompt::g_auto_confirm_for_tests =
-      ExtensionInstallPrompt::CANCEL;
+  install_auto_confirm_.reset();  // Destroy any old override first.
+  install_auto_confirm_.reset(new extensions::ScopedTestDialogAutoConfirm(
+      extensions::ScopedTestDialogAutoConfirm::CANCEL));
 }