Adds Compose Email Settings UI for deprecating Native App Launcher

ios/chrome/browser/web/mailto_url_rewriter_unittest.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 "ios/chrome/browser/web/mailto_handler.h"
-#import "ios/chrome/browser/web/mailto_handler_gmail.h"
+#import "ios/chrome/browser/web/fake_mailto_handler_helpers.h"
 #import "ios/chrome/browser/web/mailto_handler_system_mail.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/gtest_mac.h"
 #include "testing/platform_test.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 namespace {
 
 // Defines the 3 valid states for ShouldAutoOpenLinks_422689480.
 enum {
   kAutoOpenLinksNotSet = 0,
   kAutoOpenLinksNo = 1,
   kAutoOpenLinksYes = 2,
 };
 NSString* const kLegacyShouldAutoOpenKey = @"ShouldAutoOpenLinks_422689480";
 NSString* const kGmailAppStoreID = @"422689480";
 
 }  // namespace
 
-#pragma mark - Gmail not installed
-
-@interface FakeMailtoHandlerGmailNotInstalled : MailtoHandlerGmail
-@end
-
-@implementation FakeMailtoHandlerGmailNotInstalled
-- (BOOL)isAvailable {
-  return NO;
-}
-@end
-
-#pragma mark - Gmail is installed
-
-@interface FakeMailtoHandlerGmailInstalled : MailtoHandlerGmail
-@end
-
-@implementation FakeMailtoHandlerGmailInstalled
-- (BOOL)isAvailable {
-  return YES;
-}
-@end
-
-#pragma mark - Test Observer object
-
-@interface RewriterObserver : NSObject<MailtoURLRewriterObserver>
-@property(nonatomic, readonly) int changeCount;
-@end
-
-@implementation RewriterObserver
-@synthesize changeCount = _changeCount;
-- (void)rewriterDidChange:(MailtoURLRewriter*)rewriter {
-  ++_changeCount;
-}
-@end
-
 #pragma mark - MailtoURLRewriter private interfaces for testing.
 
 @interface MailtoURLRewriter ()
 + (void)resetDefaultHandlerIDForTesting;
 - (void)addMailtoApps:(NSArray<MailtoHandler*>*)handlerApps;
 @end
 
 #pragma mark - Unit Test Cases
 
 class MailtoURLRewriterTest : public PlatformTest {
@@ skipping 47 matching lines @@
   [rewriter setDefaultHandlerID:otherHandlerID];
 
   // Create a new MailtoURLRewriter object and verify that the current
   // default is the |otherHandlerID| set in the previous step.
   MailtoURLRewriter* rewriter2 = [[MailtoURLRewriter alloc] init];
   [rewriter2 addMailtoApps:@[ systemMailHandler, fakeGmailHandler ]];
   EXPECT_NSEQ(otherHandlerID, [rewriter2 defaultHandlerID]);
 }
 
 TEST_F(MailtoURLRewriterTest, TestChangeObserver) {
-  RewriterObserver* observer = [[RewriterObserver alloc] init];
+  CountingMailtoURLRewriterObserver* observer =
+      [[CountingMailtoURLRewriterObserver alloc] init];
   ASSERT_EQ(0, [observer changeCount]);
 
   // Sets up a MailtoURLRewriter object. The default handler is Gmail app
   // because |fakeGmailHandler| reports that it is "installed".
   MailtoURLRewriter* rewriter = [[MailtoURLRewriter alloc] init];
   MailtoHandler* systemMailHandler = [[MailtoHandlerSystemMail alloc] init];
   MailtoHandler* fakeGmailHandler =
       [[FakeMailtoHandlerGmailInstalled alloc] init];
   [rewriter addMailtoApps:@[ systemMailHandler, fakeGmailHandler ]];
   EXPECT_NSEQ([fakeGmailHandler appStoreID], [rewriter defaultHandlerID]);
@@ skipping 111 matching lines @@
       [[FakeMailtoHandlerGmailInstalled alloc] init];
 
   // Sets up a MailtoURLRewriter for testing.
   MailtoURLRewriter* rewriter = [[MailtoURLRewriter alloc] init];
   MailtoHandler* systemMailHandler = [[MailtoHandlerSystemMail alloc] init];
   [rewriter addMailtoApps:@[ systemMailHandler, fakeGmailHandler ]];
 
   // Verify that MailtoURLRewriter will use Gmail app.
   EXPECT_NSEQ(kGmailAppStoreID, [rewriter defaultHandlerID]);
 }