Use oobe-illustration class for pin setup illustraion

Bug: 1023397
Change-Id: Iaecffb245ca0da14a8a048966690534eb92f3046
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1912122Reviewed-by: Roman Sorokin [CET] <rsorokin@chromium.org>
Commit-Queue: Denis Kuznetsov [CET] <antrim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#714532}

chrome/browser/resources/chromeos/login/discover/modules/discover_module_pin_setup.css

@@ -10,9 +10,3 @@
 setup-pin-keyboard {
   margin-top: 17px;
 }
-
-#done-illustration {
-  height: 264px;
-  margin-top: 38px; /* 64px from subtitle baseline. */
-  width: 264px;
-}

chrome/browser/resources/chromeos/login/discover/modules/discover_module_pin_setup.html

@@ -110,6 +110,7 @@
               is-incognito-ui>
           </setup-pin-keyboard>
         <img id="done-illustration" hidden="[[isStepHidden_(step_, 'done')]]"
+            class="oobe-illustration"
             srcset="images/pin_illustration_1x.svg 1x,
                     images/pin_illustration_2x.svg 2x">
       </div>

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

@@ -22,3 +22,9 @@
   border-radius: 4px;
   box-shadow: 0 24px 24px rgba(0, 0, 0, .24), 0 0 24px rgba(0, 0, 0, .12);
 }
+
+.oobe-illustration {
+  max-height: -webkit-fill-available;
+  max-width: -webkit-fill-available;
+  object-fit: contain;
+}

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

@@ -116,9 +116,3 @@
   right: 0;
   top: 0;
 }
-
-.oobe-illustration {
-  max-height: -webkit-fill-available;
-  max-width: -webkit-fill-available;
-  object-fit: contain;
-}