Adds Compose Email Settings UI for deprecating Native App Launcher

ios/chrome/browser/web/mailto_url_rewriter.mm

 // Copyright 2017 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/web/mailto_url_rewriter.h"
 
 #import "base/logging.h"
 #import "ios/chrome/browser/web/mailto_handler.h"
 #import "ios/chrome/browser/web/mailto_handler_gmail.h"
 #import "ios/chrome/browser/web/mailto_handler_system_mail.h"
@@ skipping 62 matching lines @@
   self = [self init];
   if (self) {
     [self addMailtoApps:@[
       [[MailtoHandlerSystemMail alloc] init], [[MailtoHandlerGmail alloc] init]
     ]];
   }
   return self;
 }
 
 - (NSArray<MailtoHandler*>*)defaultHandlers {
-  return [_handlers allValues];
+  return [[_handlers allValues]
+      sortedArrayUsingComparator:^NSComparisonResult(
+          MailtoHandler* _Nonnull obj1, MailtoHandler* _Nonnull obj2) {
+        return [[obj1 appName] compare:[obj2 appName]];
+      }];
 }
 
 - (NSString*)defaultHandlerID {
   NSString* value = [[NSUserDefaults standardUserDefaults]
       stringForKey:kMailtoDefaultHandlerKey];
   return value ? value : [[self class] systemMailApp];
 }
 
 - (void)setDefaultHandlerID:(NSString*)appStoreID {
   DCHECK([appStoreID length]);
@@ skipping 114 matching lines @@
   if ([defaults objectForKey:kMailtoDefaultHandlerKey])
     return;
 
   NSString* const kGmailAppStoreID = @"422689480";
   MailtoHandler* gmailHandler = _handlers[kGmailAppStoreID];
   if ([gmailHandler isAvailable])
     [defaults setObject:kGmailAppStoreID forKey:kMailtoDefaultHandlerKey];
 }
 
 @end