[iOS][PageInfo] Updates navbar title

This CL uses a UILabel to display the site URL instead of an NSString,
to control auto-resizing.

Bug: 1104198
Change-Id: I9c0d508ed209d6bd598584b6ed74a8ecca4b0510
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2603749
Commit-Queue: Ewann Pellé <ewannpv@chromium.org>
Reviewed-by: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#841426}

ios/chrome/browser/ui/page_info/page_info_view_controller.mm

@@ -68,9 +68,9 @@ float kPaddingSecurityHeader = 28.0f;
 - (void)viewDidLoad {
   [super viewDidLoad];
 
+  self.navigationItem.titleView =
+      [self titleViewLabelForURL:self.pageInfoSecurityDescription.siteURL];
   self.title = l10n_util::GetNSString(IDS_IOS_PAGE_INFO_SITE_INFORMATION);
-  self.navigationItem.prompt = self.pageInfoSecurityDescription.siteURL;
-  self.navigationController.navigationBar.prefersLargeTitles = NO;
   self.tableView.accessibilityIdentifier = kPageInfoViewAccessibilityIdentifier;
 
   UIBarButtonItem* dismissButton = [[UIBarButtonItem alloc]
@@ -147,4 +147,17 @@ float kPaddingSecurityHeader = 28.0f;
   [self.handler showSecurityHelpPage];
 }
 
+#pragma mark - Private
+
+// Returns the navigationItem titleView for |siteURL|.
+- (UILabel*)titleViewLabelForURL:(NSString*)siteURL {
+  UILabel* labelURL = [[UILabel alloc] init];
+  labelURL.lineBreakMode = NSLineBreakByTruncatingHead;
+  labelURL.font = [UIFont preferredFontForTextStyle:UIFontTextStyleBody];
+  labelURL.text = siteURL;
+  labelURL.adjustsFontSizeToFitWidth = YES;
+  labelURL.minimumScaleFactor = 0.7;
+  return labelURL;
+}
+
 @end