Navi Onboarding: go to email-interstitial even if users don't sign in

Bug: 905503
Change-Id: Ic886e1b5946ffdbca69d5cb33f573d79437b84ae
Reviewed-on: https://chromium-review.googlesource.com/c/1336752
Commit-Queue: Scott Chen <scottchen@chromium.org>
Reviewed-by: Hector Carmona <hcarmona@chromium.org>
Cr-Commit-Position: refs/heads/master@{#608603}

chrome/browser/resources/welcome/onboarding_welcome/signin_view.js

@@ -11,28 +11,47 @@ Polymer({
   shouldShowEmailInterstitial_:
       loadTimeData.getBoolean('showEmailInterstitial'),
 
+  /** @private {?welcome.WelcomeBrowserProxy} */
+  welcomeBrowserProxy_: null,
+
+  /** @override */
+  ready: function() {
+    this.welcomeBrowserProxy_ = welcome.WelcomeBrowserProxyImpl.getInstance();
+  },
+
   /**
-   * When the user clicks sign-in, check whether or not they previously
-   * selected an email provider they prefer to use. If so, direct them back to
-   * the email-interstitial page, otherwise let it direct to NTP.
+   * @return {?string}
    * @private
    */
-  onSignInClick_: function() {
-    let redirectUrl = null;
-
+  getTargetUrl_: function() {
     const savedProvider =
         nux.NuxEmailProxyImpl.getInstance().getSavedProvider();
     if (savedProvider != undefined && this.shouldShowEmailInterstitial_) {
-      redirectUrl =
-          `chrome://welcome/email-interstitial?provider=${savedProvider}`;
+      return `chrome://welcome/email-interstitial?provider=${savedProvider}`;
+    } else {
+      return null;
     }
+  },
 
-    welcome.WelcomeBrowserProxyImpl.getInstance().handleActivateSignIn(
-        redirectUrl);
+  /**
+   * When the user clicks sign-in, check whether or not they previously
+   * selected an email provider they prefer to use. If so, direct them back to
+   * the email-interstitial page, otherwise let it direct to NTP.
+   * @private
+   */
+  onSignInClick_: function() {
+    this.welcomeBrowserProxy_.handleActivateSignIn(this.getTargetUrl_());
   },
 
   /** @private */
   onNoThanksClick_: function() {
-    welcome.navigateToNextStep();
+    // It's safe to assume sign-view is always going to be the last step, so
+    // either go to the target url directly, or go to NTP directly.
+    const targetUrl = this.getTargetUrl_();
+    if (targetUrl) {
+      this.welcomeBrowserProxy_.goToURL(targetUrl);
+    } else {
+      this.welcomeBrowserProxy_.goToNewTabPage();
+    }
   }
 });