Fix status bar appearance and title view layouting on iOS 13 (#5604)

* Sets the window background color to the system's one for dark mode support

* Fix title layouting on iOS 13

lib/ios/RNNTitleViewHelper.m

 
 @implementation RNNTitleView
 
+- (void)layoutSubviews {
+	CGFloat heightSum = _titleLabel.frame.size.height + _subtitleLabel.frame.size.height;
+	CGFloat yOffset = (self.frame.size.height - heightSum) / 2;
+	
+	[_titleLabel setFrame:CGRectMake(0, yOffset, self.frame.size.width, _titleLabel.frame.size.height)];
+	[_subtitleLabel setFrame:CGRectMake(0, yOffset+_titleLabel.frame.size.height, self.frame.size
+										.width, _subtitleLabel.frame.size.height)];
+}
 
 @end
 
 	
 	self.titleView = [[RNNTitleView alloc] initWithFrame:navigationBarBounds];
 	self.titleView.backgroundColor = [UIColor clearColor];
-	self.titleView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin;
+	self.titleView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleHeight;
 	self.titleView.clipsToBounds = YES;
 	
 	if (self.subtitle) {
 	UILabel *subtitleLabel = [[UILabel alloc] initWithFrame:subtitleFrame];
 	subtitleLabel.textAlignment = NSTextAlignmentCenter;
 	subtitleLabel.backgroundColor = [UIColor clearColor];
-	subtitleLabel.autoresizingMask = self.titleView.autoresizingMask;
+	subtitleLabel.autoresizingMask = UIViewAutoresizingFlexibleWidth;
 	
 	NSDictionary* fontAttributes = [RNNFontAttributesCreator createWithFontFamily:[_subtitleOptions.fontFamily getWithDefaultValue:nil] fontSize:[_subtitleOptions.fontSize getWithDefaultValue:nil] fontWeight:[_subtitleOptions.fontWeight getWithDefaultValue:nil] color:[_subtitleOptions.color getWithDefaultValue:nil]];
 	[subtitleLabel setAttributedText:[[NSAttributedString alloc] initWithString:self.subtitle attributes:fontAttributes]];
 	titleLabel.textAlignment = NSTextAlignmentCenter;
 	titleLabel.backgroundColor = [UIColor clearColor];
 	
-	titleLabel.autoresizingMask = self.titleView.autoresizingMask;
+	titleLabel.autoresizingMask = UIViewAutoresizingFlexibleWidth;
 	
 	NSDictionary* fontAttributes = [RNNFontAttributesCreator createWithFontFamily:[_titleOptions.fontFamily getWithDefaultValue:nil] fontSize:[_titleOptions.fontSize getWithDefaultValue:nil] fontWeight:[_titleOptions.fontWeight getWithDefaultValue:nil] color:[_subtitleOptions.color getWithDefaultValue:nil]];
 	[titleLabel setAttributedText:[[NSAttributedString alloc] initWithString:self.title attributes:fontAttributes]];

lib/ios/ReactNativeNavigation.m

 
 - (UIWindow *)initializeKeyWindow {
 	UIWindow* keyWindow = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
-	keyWindow.backgroundColor = [UIColor whiteColor];
+	if (@available(iOS 13.0, *)) {
+		keyWindow.backgroundColor = [UIColor systemBackgroundColor];
+	} else {
+		keyWindow.backgroundColor = [UIColor whiteColor];
+	}
 	UIApplication.sharedApplication.delegate.window = keyWindow;
 	
 	return keyWindow;