Reset only invalid custom margins.

BUG=332183

Review URL: https://codereview.chromium.org/131013005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244086 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/resources/print_preview/data/print_ticket_store.js

@@ -423,10 +423,11 @@ cr.define('print_preview', function() {
         cr.dispatchSimpleEvent(this, PrintTicketStore.EventType.INITIALIZE);
       } else {
         // Reset user selection for certain ticket items.
-        this.customMargins_.updateValue(null);
-
         if (this.marginsType_.getValue() ==
-            print_preview.ticket_items.MarginsType.Value.CUSTOM) {
+            print_preview.ticket_items.MarginsType.Value.CUSTOM &&
+            !this.customMargins_.wouldValueBeValid(
+                 this.customMargins_.getValue())) {
+          this.customMargins_.updateValue(null);
           this.marginsType_.updateValue(
               print_preview.ticket_items.MarginsType.Value.DEFAULT);
         }

chrome/test/data/webui/print_preview.js

@@ -722,7 +722,7 @@ TEST_F('PrintPreviewWebUITest', 'TestPrinterChangeUpdatesPreview', function() {
 
   var previewGenerator = mock(print_preview.PreviewGenerator);
   printPreview.previewArea_.previewGenerator_ = previewGenerator.proxy();
-  previewGenerator.expects(exactly(6)).requestPreview();
+  previewGenerator.expects(atLeastOnce()).requestPreview();
 
   var barDestination;
   var destinations = printPreview.destinationStore_.destinations;