[Extensions UI] Initially disabled OK button for extension install prompts.

chrome/browser/ui/views/extensions/extension_install_dialog_view_browsertest.cc

Index: chrome/browser/ui/views/extensions/extension_install_dialog_view_browsertest.cc
diff --git a/chrome/browser/ui/views/extensions/extension_install_dialog_view_browsertest.cc b/chrome/browser/ui/views/extensions/extension_install_dialog_view_browsertest.cc
index 0ac3d9395ca43204acb70a7187590c9c9f47ed6b..3ac2aad73a91ff6b16669548fa43c09893c00b2d 100644
--- a/chrome/browser/ui/views/extensions/extension_install_dialog_view_browsertest.cc
+++ b/chrome/browser/ui/views/extensions/extension_install_dialog_view_browsertest.cc
@@ -7,6 +7,7 @@
 #include <utility>
 
 #include "base/macros.h"
+#include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/extensions/extension_browsertest.h"
 #include "chrome/browser/extensions/extension_icon_manager.h"
@@ -202,3 +203,23 @@ IN_PROC_BROWSER_TEST_F(ExtensionInstallDialogViewTest, NotifyDelegate) {
     EXPECT_EQ(ExtensionInstallPrompt::Result::USER_CANCELED, helper.result());
   }
 }
+
+// Verifies that the "Add extension" button is disabled initally, but re-enabled
+// after a short time delay.
+IN_PROC_BROWSER_TEST_F(ExtensionInstallDialogViewTest, InstallButtonDelay) {
+  ExtensionInstallDialogView::SetInstallButtonDelayForTesting(0);
+  ExtensionInstallPromptTestHelper helper;
+  views::DialogDelegateView* delegate_view = CreateAndShowPrompt(&helper);
+
+  // Check that dialog is visible.
+  EXPECT_TRUE(delegate_view->visible());
+
+  // Check initial button states.
+  EXPECT_FALSE(delegate_view->IsDialogButtonEnabled(ui::DIALOG_BUTTON_OK));
+  EXPECT_TRUE(delegate_view->IsDialogButtonEnabled(ui::DIALOG_BUTTON_CANCEL));
+
+  // Check OK button state after timeout to verify that it is re-enabled.
+  base::RunLoop().RunUntilIdle();
+  EXPECT_TRUE(delegate_view->IsDialogButtonEnabled(ui::DIALOG_BUTTON_OK));
+  delegate_view->Close();
+}