From 63f2ef4d7feffbe2407722882b8dff8223189e9a Mon Sep 17 00:00:00 2001
From: nename0 <26363498+nename0@users.noreply.github.com>
Date: Tue, 2 Oct 2018 22:37:56 +0200
Subject: [PATCH] pref(table): prevent unnecessary reflow with sticky row
 (#12786)

The offset of a sticky row is calculated by summing up the heights of
the previous sticky rows. As the access to the height causes a forced
reflow this is now skipped when there is only one row.
---
 src/cdk/table/sticky-styler.ts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/cdk/table/sticky-styler.ts b/src/cdk/table/sticky-styler.ts
index 763cb0acc0e..f0fca155b40 100644
--- a/src/cdk/table/sticky-styler.ts
+++ b/src/cdk/table/sticky-styler.ts
@@ -140,6 +140,10 @@ export class StickyStyler {
         this._addStickyStyle(row, position, stickyHeight);
       }
 
+      if (rowIndex === rows.length - 1) {
+        // prevent unnecessary reflow from getBoundingClientRect()
+        return;
+      }
       stickyHeight += row.getBoundingClientRect().height;
     }
   }