Add UINavigationController and settings bar button to AppRTCMobile.

The navigation controller is used to display the title of the app
and to feature the settings button.

This  work is foundation for adding settings screen to the app (see webrtc:6473 for more info)

BUG=webrtc:6618, webrtc:6473

Review-Url: https://codereview.webrtc.org/2455363002
Cr-Commit-Position: refs/heads/master@{#14816}

webrtc/examples/BUILD.gn

@@ -269,6 +269,8 @@ if (is_ios || (is_mac && target_cpu != "x86")) {
         "objc/AppRTCMobile/ios/resources/ic_call_end_black_24dp@2x.png",
         "objc/AppRTCMobile/ios/resources/ic_clear_black_24dp.png",
         "objc/AppRTCMobile/ios/resources/ic_clear_black_24dp@2x.png",
+        "objc/AppRTCMobile/ios/resources/ic_settings_black_24dp.png",
+        "objc/AppRTCMobile/ios/resources/ic_settings_black_24dp@2x.png",
         "objc/AppRTCMobile/ios/resources/ic_surround_sound_black_24dp.png",
         "objc/AppRTCMobile/ios/resources/ic_surround_sound_black_24dp@2x.png",
         "objc/AppRTCMobile/ios/resources/ic_switch_video_black_24dp.png",

webrtc/examples/objc/AppRTCMobile/ios/ARDAppDelegate.m

@@ -31,7 +31,11 @@
   _window =  [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
   [_window makeKeyAndVisible];
   ARDMainViewController *viewController = [[ARDMainViewController alloc] init];
-  _window.rootViewController = viewController;
+
+  UINavigationController *root =
+      [[UINavigationController alloc] initWithRootViewController:viewController];
+  root.navigationBar.translucent = NO;
+  _window.rootViewController = root;
 
 #if defined(NDEBUG)
   // In debug builds the default level is LS_INFO and in non-debug builds it is

webrtc/examples/objc/AppRTCMobile/ios/ARDMainView.m

@@ -114,7 +114,6 @@ static CGFloat const kCallControlMargin = 8;
 @end
 
 @implementation ARDMainView {
-  UILabel *_appLabel;
   ARDRoomTextField *_roomText;
   UILabel *_callOptionsLabel;
   UISwitch *_audioOnlySwitch;
@@ -136,13 +135,6 @@ static CGFloat const kCallControlMargin = 8;
 
 - (instancetype)initWithFrame:(CGRect)frame {
   if (self = [super initWithFrame:frame]) {
-    _appLabel = [[UILabel alloc] initWithFrame:CGRectZero];
-    _appLabel.text = @"AppRTCMobile";
-    _appLabel.font = [UIFont fontWithName:@"Roboto" size:34];
-    _appLabel.textColor = [UIColor colorWithWhite:0 alpha:.2];
-    [_appLabel sizeToFit];
-    [self addSubview:_appLabel];
-
     _roomText = [[ARDRoomTextField alloc] initWithFrame:CGRectZero];
     [self addSubview:_roomText];
 
@@ -263,11 +255,8 @@ static CGFloat const kCallControlMargin = 8;
   CGRect bounds = self.bounds;
   CGFloat roomTextWidth = bounds.size.width - 2 * kRoomTextFieldMargin;
   CGFloat roomTextHeight = [_roomText sizeThatFits:bounds.size].height;
-  _roomText.frame = CGRectMake(kRoomTextFieldMargin,
-                               kStatusBarHeight + kRoomTextFieldMargin,
-                               roomTextWidth,
-                               roomTextHeight);
-  _appLabel.center = CGPointMake(CGRectGetMidX(bounds), CGRectGetMidY(bounds));
+  _roomText.frame =
+      CGRectMake(kRoomTextFieldMargin, kRoomTextFieldMargin, roomTextWidth, roomTextHeight);
 
   CGFloat callOptionsLabelTop =
       CGRectGetMaxY(_roomText.frame) + kCallControlMargin * 4;

webrtc/examples/objc/AppRTCMobile/ios/ARDMainViewController.m

@@ -21,6 +21,8 @@
 #import "ARDMainView.h"
 #import "ARDVideoCallViewController.h"
 
+static NSString *barButtonImageString = @"ic_settings_black_24dp.png";
+
 @interface ARDMainViewController () <
     ARDMainViewDelegate,
     ARDVideoCallViewControllerDelegate,
@@ -34,9 +36,11 @@
 }
 
 - (void)loadView {
+  self.title = @"AppRTC Mobile";
   _mainView = [[ARDMainView alloc] initWithFrame:CGRectZero];
   _mainView.delegate = self;
   self.view = _mainView;
+  [self addSettingsBarButton];
 
   RTCAudioSessionConfiguration *webRTCConfig =
       [RTCAudioSessionConfiguration webRTCConfiguration];
@@ -51,6 +55,15 @@
   [self setupAudioPlayer];
 }
 
+- (void)addSettingsBarButton {
+  UIBarButtonItem *settingsButton =
+      [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:barButtonImageString]
+                                       style:UIBarButtonItemStylePlain
+                                      target:self
+                                      action:@selector(showSettings:)];
+  self.navigationItem.rightBarButtonItem = settingsButton;
+}
+
 #pragma mark - ARDMainViewDelegate
 
 - (void)mainView:(ARDMainView *)mainView
@@ -155,6 +168,8 @@
 }
 
 #pragma mark - Private
+- (void)showSettings:(id)sender {
+}
 
 - (void)configureAudioSession {
   RTCAudioSessionConfiguration *configuration =