OOBE: Enrollment screen polishing

* Don't shrink SAML window - it hosts oobe-dialog anyway (which has
fixed size)
* Remove outdated css rules - it caused buttons be white on white (so
not visible but active)
* Stop showing back button on top at all - the screen has bottom back
butotn now
* Fix glitch with refresh button - it was shown for a second when
isManualEnrollment_ was not yet defined.

Bug: 965392
Change-Id: I680d7471a53a4e8c17aae4c37433633e120c11a3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1640643Reviewed-by: Denis Kuznetsov <antrim@chromium.org>
Commit-Queue: Roman Sorokin [CET] <rsorokin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#665540}

chrome/browser/resources/chromeos/login/oobe_screen_oauth_enrollment.css

@@ -10,7 +10,6 @@
 
 #oauth-enrollment.saml {
   padding-top: 44px;
-  width: 562px;
 }
 
 #oauth-enroll-step-contents {
@@ -65,7 +64,7 @@
 .oauth-enroll-step-message {
   display: inline-block;
   padding-top: 20px;
-  text-align: left;
+  text-align: start;
   vertical-align: top;
 }
 
@@ -117,14 +116,3 @@
   top: 0;
   z-index: 1;
 }
-
-.oauth-enroll-state-signin #oauth-enroll-navigation,
-.oauth-enroll-state-ad-join #oauth-enroll-navigation,
-.oauth-enroll-state-working #oauth-enroll-navigation {
-  color: white;
-}
-
-#oauth-enrollment.saml #oauth-enroll-navigation {
-  color: rgba(0, 0, 0, .54);
-}
-

chrome/browser/resources/chromeos/login/oobe_screen_oauth_enrollment.js

@@ -220,11 +220,8 @@ login.createScreen('OAuthEnrollmentScreen', 'oauth-enrollment', function() {
       this.navigation_.addEventListener('close', this.cancel.bind(this));
       this.navigation_.addEventListener('refresh', this.cancel.bind(this));
 
-      this.navigation_.addEventListener(
-          'back', this.onBackButtonClicked_.bind(this, false));
-
       $('oobe-signin-back-button')
-          .addEventListener('tap', this.onBackButtonClicked_.bind(this, true));
+          .addEventListener('tap', this.onBackButtonClicked_.bind(this));
 
 
       $('oauth-enroll-learn-more-link')
@@ -472,13 +469,12 @@ login.createScreen('OAuthEnrollmentScreen', 'oauth-enrollment', function() {
      * Skips the device attribute update,
      * shows the successful enrollment step.
      */
-    onBackButtonClicked_: function(cancelOnClick) {
-      this.navigation_.backVisible = false;
+    onBackButtonClicked_: function() {
       if (this.currentStep_ == STEP_SIGNIN) {
         if (this.lastBackMessageValue_) {
           this.lastBackMessageValue_ = false;
           $('oauth-enroll-auth-view').back();
-        } else if (cancelOnClick) {
+        } else {
           this.cancel();
         }
       }
@@ -502,17 +498,15 @@ login.createScreen('OAuthEnrollmentScreen', 'oauth-enrollment', function() {
      * @type {boolean}
      */
     isAtTheBeginning: function() {
-      return !this.navigation_.backVisible && this.currentStep_ == STEP_SIGNIN;
+      return !this.lastBackMessageValue_ && this.currentStep_ == STEP_SIGNIN;
     },
 
     /**
      * Updates visibility of navigation buttons.
      */
     updateControlsState: function() {
-      this.navigation_.backVisible =
-          this.currentStep_ == STEP_SIGNIN && this.lastBackMessageValue_;
       this.navigation_.refreshVisible =
-          this.isAtTheBeginning() && !this.isManualEnrollment_;
+          this.isAtTheBeginning() && this.isManualEnrollment_ === false;
       this.navigation_.closeVisible =
           (this.currentStep_ == STEP_ERROR && !this.navigation_.refreshVisible)
           || this.currentStep_ == STEP_LICENSE_TYPE;