Add test for pseudo background image lazyload

Bug: 932634 Change-Id: Icb5009f436181c1686885dbbfea724dc8a67b77a Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1522926Reviewed-by: Tarun Bansal <tbansal@chromium.org> Commit-Queue: rajendrant <rajendrant@chromium.org> Cr-Commit-Position: refs/heads/master@{#642374}

Add test for pseudo background image lazyload
Bug: 932634 Change-Id: Icb5009f436181c1686885dbbfea724dc8a67b77a Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1522926Reviewed-by: Tarun Bansal <tbansal@chromium.org> Commit-Queue: rajendrant <rajendrant@chromium.org> Cr-Commit-Position: refs/heads/master@{#642374}
15329dc3 · rajendrant · Commit Bot · ef3fbbf0 · 15329dc3 · 15329dc3
Commit 15329dc3 authored Mar 20, 2019 by rajendrant Committed by Commit Bot Mar 20, 2019
2 changed files
--- a/chrome/browser/previews/lazyload_browsertest.cc
+++ b/chrome/browser/previews/lazyload_browsertest.cc
@@ -43,3 +43,20 @@ IN_PROC_BROWSER_TEST_F(LazyLoadBrowserTest, CSSBackgroundImageDeferred) {

 // TODO(rajendrant): Add a test that checks if the deferred image is loaded when
 // user scrolls near it.
+
+IN_PROC_BROWSER_TEST_F(LazyLoadBrowserTest, CSSPseudoBackgroundImageLoaded) {
+  ASSERT_TRUE(embedded_test_server()->Start());
+  base::HistogramTester histogram_tester;
+  ui_test_utils::NavigateToURL(
+      browser(), embedded_test_server()->GetURL(
+                     "/lazyload/css-pseudo-background-image.html"));
+
+  base::RunLoop().RunUntilIdle();
+  // Navigate away to finish the histogram recording.
+  ui_test_utils::NavigateToURL(browser(), GURL(url::kAboutBlankURL));
+
+  // Verify that the image bucket has substantial kilobytes recorded.
+  EXPECT_GE(30 /* KB */, histogram_tester.GetBucketCount(
+                             "DataUse.ContentType.UserTrafficKB",
+                             data_use_measurement::DataUseUserData::IMAGE));
+}
--- a/chrome/test/data/lazyload/css-pseudo-background-image.html
+++ b/chrome/test/data/lazyload/css-pseudo-background-image.html
+<!DOCTYPE html>
+<html>
+<style>
+body::before {
+    position: absolute;
+    width: 100%;
+    height: 100%;
+    background-image: url("images/fruit1.jpg");
+}
+</style>
+<body>
+</body>
+</html>