Show all mailto: handlers, but dim unavailable ones.

ios/chrome/browser/ui/settings/content_settings_collection_view_controller_unittest.mm

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "ios/chrome/browser/ui/settings/content_settings_collection_view_controller.h"
 
 #include "ios/chrome/browser/browser_state/test_chrome_browser_state.h"
 #include "ios/chrome/browser/experimental_flags.h"
 #import "ios/chrome/browser/ui/collection_view/cells/collection_view_detail_item.h"
 #import "ios/chrome/browser/ui/collection_view/collection_view_controller_test.h"
@@ skipping 26 matching lines @@
   web::TestWebThreadBundle thread_bundle_;
   std::unique_ptr<TestChromeBrowserState> chrome_browser_state_;
 };
 
 TEST_F(ContentSettingsCollectionViewControllerTest, TestModel) {
   CreateController();
   CheckController();
   CheckTitleWithId(IDS_IOS_CONTENT_SETTINGS_TITLE);
 
   ASSERT_EQ(1, NumberOfSections());
-  // Compose Email section is shown only if experiment is turned on and
-  // there are enough number of available mailto: URL handlers.
-  int number_of_handlers =
-      [[[[MailtoURLRewriter alloc] initWithStandardHandlers] defaultHandlers]
-          count];
+  // Compose Email section is shown only if experiment is turned on.
   bool show_compose_email_section =
-      experimental_flags::IsNativeAppLauncherEnabled() &&
-      number_of_handlers > 1;
+      !experimental_flags::IsNativeAppLauncherEnabled();

[pkl (ping after 24h if needed), 2017/05/19 18:22:03]

Note that there was a bug which was masked by the other condition.

   int expectedNumberOfItems = show_compose_email_section ? 3 : 2;
   EXPECT_EQ(expectedNumberOfItems, NumberOfItemsInSection(0));
   CheckDetailItemTextWithIds(IDS_IOS_BLOCK_POPUPS, IDS_IOS_SETTING_ON, 0, 0);
   CheckDetailItemTextWithIds(IDS_IOS_TRANSLATE_SETTING, IDS_IOS_SETTING_ON, 0,
                              1);
   if (show_compose_email_section) {
     CollectionViewDetailItem* item = GetCollectionViewItem(0, 2);
     EXPECT_NSEQ(l10n_util::GetNSString(IDS_IOS_COMPOSE_EMAIL_SETTING),
                 item.text);
   }
 }
 
 }  // namespace