1 files changed, 13 insertions, 0 deletions
diff --git a/testing/web-platform/tests/paint-timing/resources/subframe-sending-paint.html b/testing/web-platform/tests/paint-timing/resources/subframe-sending-paint.html
new file mode 100644
index 0000000000..f372bd6f4f
--- /dev/null
+++ b/testing/web-platform/tests/paint-timing/resources/subframe-sending-paint.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<script>
+  self.addEventListener('message', function(e) {
+    // Send paint-timing entries upon receiving a message.
+    const paintEntries = performance.getEntriesByType('paint');
+    let entryContents = paintEntries.length + '';
+    for (let i = 0; i < paintEntries.length; i++) {
+      const entry = paintEntries[i];
+      entryContents += ' ' + entry.entryType + ' '  + entry.name;
+    }
+    parent.postMessage(entryContents, '*');
+  });
+</script>