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

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

Index: chrome/browser/ui/cocoa/extensions/extension_install_view_controller_unittest.mm
diff --git a/chrome/browser/ui/cocoa/extensions/extension_install_view_controller_unittest.mm b/chrome/browser/ui/cocoa/extensions/extension_install_view_controller_unittest.mm
index a15c22a3571cfdfca51a8cbbb95e558c4380d575..733d2766d77d1441e1269de872929b979ae53c2d 100644
--- a/chrome/browser/ui/cocoa/extensions/extension_install_view_controller_unittest.mm
+++ b/chrome/browser/ui/cocoa/extensions/extension_install_view_controller_unittest.mm
@@ -15,6 +15,7 @@
 #include "chrome/browser/ui/browser.h"
 #import "chrome/browser/ui/cocoa/extensions/extension_install_prompt_test_utils.h"
 #include "chrome/browser/ui/cocoa/test/cocoa_profile_test.h"
+#include "chrome/browser/ui/cocoa/test/run_loop_testing.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/permissions/permission_message_provider.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -377,3 +378,31 @@ TEST_F(ExtensionInstallViewControllerTest, PermissionsDetails) {
                           objectValueForTableColumn:nil
                                              byItem:[outlineView itemAtRow:2]]);
 }
+
+// Test that install button is disabled for a short time period.
+TEST_F(ExtensionInstallViewControllerTest, DelayedInstalls) {
+  [ExtensionInstallViewController setInstallDelayForTesting:0];
+  MockExtensionInstallViewDelegate delegate;
+
+  std::unique_ptr<ExtensionInstallPrompt::Prompt> prompt(
+      chrome::BuildExtensionInstallPrompt(extension_.get()));
+
+  base::scoped_nsobject<ExtensionInstallViewController> controller(
+      [[ExtensionInstallViewController alloc]
+          initWithProfile:profile()
+                navigator:browser()
+                 delegate:&delegate
+                   prompt:std::move(prompt)]);
+
+  [controller view];  // Force nib load.
+
+  // Check initial button states.
+  NSButton* cancelButton_ = [controller cancelButton];
+  NSButton* okButton_ = [controller okButton];
+  EXPECT_TRUE([cancelButton_ isEnabled]);
+  EXPECT_FALSE([okButton_ isEnabled]);
+
+  // Check OK button state after timeout to verifiy that it is enabled.
+  chrome::testing::NSRunLoopRunAllPending();
+  EXPECT_TRUE([okButton_ isEnabled]);
+}