From f8e9796421cb05ebee3a06238b748ad74f75033c Mon Sep 17 00:00:00 2001
From: Russell Bicknell <bicknellr@google.com>
Date: Fri, 5 Mar 2021 13:13:26 -0800
Subject: [PATCH] Upstream cl/326093618: Fix incorrect height on deselection.

---
 paper-dropdown-menu-light.js        |  6 ++++++
 test/paper-dropdown-menu-light.html | 12 +++++++++++-
 test/paper-dropdown-menu.html       | 10 ++++++++++
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/paper-dropdown-menu-light.js b/paper-dropdown-menu-light.js
index 7fc47a9..0576f12 100644
--- a/paper-dropdown-menu-light.js
+++ b/paper-dropdown-menu-light.js
@@ -586,5 +586,11 @@ Polymer({
       this.$.input.textContent = this.value;
     }
     this._setHasContent(!!this.value);
+    if (!this.hasContent) {
+      // If there is no content then reset to '&nbsp', which is required
+      // for the input height to be correct. Uses 'xa0' instead of '&nbsp' to
+      // avoid innerHTML.
+      this.$.input.textContent = '\xa0';
+    }
   }
 });
diff --git a/test/paper-dropdown-menu-light.html b/test/paper-dropdown-menu-light.html
index dcd5508..8598474 100644
--- a/test/paper-dropdown-menu-light.html
+++ b/test/paper-dropdown-menu-light.html
@@ -153,6 +153,16 @@
           content.selected = null;
           expect(dropdownMenu.selectedItem).to.be.equal(null);
         });
+
+        test('maintains its size', function() {
+          const initialRect = dropdownMenu.getBoundingClientRect();
+
+          content.selected = null;
+
+          const deselectedRect = dropdownMenu.getBoundingClientRect();
+          expect(deselectedRect.width).closeTo(initialRect.width, 1);
+          expect(deselectedRect.height).closeTo(initialRect.height, 1);
+        });
       });
 
       suite('validation', function() {
@@ -236,4 +246,4 @@
   </script>
 
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/test/paper-dropdown-menu.html b/test/paper-dropdown-menu.html
index 5c164ee..7b36f17 100644
--- a/test/paper-dropdown-menu.html
+++ b/test/paper-dropdown-menu.html
@@ -175,6 +175,16 @@
           content.selected = null;
           expect(dropdownMenu.selectedItem).to.be.equal(null);
         });
+
+        test('maintains its size', function() {
+          const initialRect = dropdownMenu.getBoundingClientRect();
+
+          content.selected = null;
+
+          const deselectedRect = dropdownMenu.getBoundingClientRect();
+          expect(deselectedRect.width).closeTo(initialRect.width, 1);
+          expect(deselectedRect.height).closeTo(initialRect.height, 1);
+        });
       });
 
       suite('validation', function() {