Expose SSL interstitial delay for captive portal detection.

Exposing kSSLInterstitialDelayInSeconds allows tests to use it directly
rather than duplicating the value of the constant.

Bug: 790934
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: If2cabdf773ce414dc966e0396847660d835c1d72
Reviewed-on: https://chromium-review.googlesource.com/806643
Commit-Queue: Mike Dougherty <michaeldo@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521712}

ios/chrome/browser/ssl/ios_ssl_error_handler.h

@@ -21,6 +21,12 @@ namespace web {
 class WebState;
 }  // namespace web
 
+// Default delay in seconds before displaying the SSL interstitial.
+// - If a "captive portal detected" result arrives during this time,
+//   a captive portal interstitial is displayed.
+// - Otherwise, an SSL interstitial is displayed.
+extern const int64_t kSSLInterstitialDelayInSeconds;
+
 // This class is responsible for deciding what type of interstitial to show for
 // an SSL validation error.
 class IOSSSLErrorHandler : public web::WebStateUserData<IOSSSLErrorHandler> {

ios/chrome/browser/ssl/ios_ssl_error_handler.mm

@@ -30,11 +30,7 @@ DEFINE_WEB_STATE_USER_DATA_KEY(IOSSSLErrorHandler);
 const char kSessionDetectionResultHistogram[] =
     "CaptivePortal.Session.DetectionResult";
 
-// Default delay in milliseconds before displaying the SSL interstitial.
-// - If a "captive portal detected" result arrives during this time,
-//   a captive portal interstitial is displayed.
-// - Otherwise, an SSL interstitial is displayed.
-const int64_t kInterstitialDelayInMilliseconds = 3000;
+const int64_t kSSLInterstitialDelayInSeconds = 3;
 
 using captive_portal::CaptivePortalDetector;
 
@@ -102,10 +98,9 @@ void IOSSSLErrorHandler::StartHandlingError() {
 
   // Default to presenting the SSL interstitial if Captive Portal detection
   // takes too long.
-  timer_.Start(
-      FROM_HERE,
-      base::TimeDelta::FromMilliseconds(kInterstitialDelayInMilliseconds), this,
-      &IOSSSLErrorHandler::ShowSSLInterstitial);
+  timer_.Start(FROM_HERE,
+               base::TimeDelta::FromSeconds(kSSLInterstitialDelayInSeconds),
+               this, &IOSSSLErrorHandler::ShowSSLInterstitial);
 }
 
 void IOSSSLErrorHandler::HandleCaptivePortalDetectionResult(