New tests case for verifying not sized template-areas use auto-{columns,rows}.

LayoutTests/fast/css-grid-layout/grid-auto-columns-rows-resolution.html

Index: LayoutTests/fast/css-grid-layout/grid-auto-columns-rows-resolution.html
diff --git a/LayoutTests/fast/css-grid-layout/grid-auto-columns-rows-resolution.html b/LayoutTests/fast/css-grid-layout/grid-auto-columns-rows-resolution.html
index 29a2b89d74b9139e2559c0337cd9c2a673f8a6af..76bac5246c766e47c3648762147f6c12e2ea3210 100644
--- a/LayoutTests/fast/css-grid-layout/grid-auto-columns-rows-resolution.html
+++ b/LayoutTests/fast/css-grid-layout/grid-auto-columns-rows-resolution.html
@@ -13,6 +13,11 @@
     grid-auto-columns: 50px;
 }
 
+.gridAreas {
+    grid-template-areas: ". ."
+                         ". placeholder";
+}
+
 .gridAutoMinMax {
     height: 1000px;
     grid-auto-rows: minmax(10%, 15px);
@@ -48,5 +53,11 @@
     </div>
 </div>
 
+<div class="unconstrainedContainer" style="position: relative">
+    <div class="grid gridAutoFixedFixed gridAreas">
+        <div style="grid-area: placeholder;" class="sizedToGridArea" data-offset-x="10" data-offset-y="20" data-expected-width="50" data-expected-height="30">XXXXX XXXXXX</div>
+    </div>
+</div>
+
 </body>
 </html>