[CRD iOS] Add the host setup instruction page

remoting/ios/app/host_setup_footer_view.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.
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+#import "remoting/ios/app/host_setup_footer_view.h"
+
+#import "ios/third_party/material_components_ios/src/components/Buttons/src/MaterialButtons.h"
+#import "ios/third_party/material_components_ios/src/components/Typography/src/MaterialTypography.h"
+#import "remoting/ios/app/app_delegate.h"
+#import "remoting/ios/app/remoting_theme.h"
+
+static const CGFloat kTopPadding = 6.f;
+
+@implementation HostSetupFooterView
+
+- (instancetype)initWithFrame:(CGRect)frame {
+  if (self = [super initWithFrame:frame]) {
+    [self commonInit];
+  }
+  return self;
+}
+
+- (void)commonInit {
+  self.backgroundColor = RemotingTheme.setupListBackgroundColor;
+
+  MDCRaisedButton* raisedButton = [[MDCRaisedButton alloc] init];
+
+  [raisedButton setTitle:@"Email link and instructions"
+                forState:UIControlStateNormal];
+  [raisedButton setTitleColor:RemotingTheme.buttonTextColor
+                     forState:UIControlStateNormal];
+  [raisedButton sizeToFit];
+  [raisedButton addTarget:self
+                   action:@selector(didTapEmailInstructions:)
+         forControlEvents:UIControlEventTouchUpInside];
+  [self addSubview:raisedButton];
+  raisedButton.translatesAutoresizingMaskIntoConstraints = NO;
+  [NSLayoutConstraint activateConstraints:@[
+    [raisedButton.centerXAnchor constraintEqualToAnchor:self.centerXAnchor],
+    [raisedButton.topAnchor constraintEqualToAnchor:self.topAnchor
+                                           constant:kTopPadding],
+  ]];
+}
+
+- (void)didTapEmailInstructions:(id)button {
+  [AppDelegate.instance emailSetupInstructions];
+}
+
+@end