Import wpt@05018e45859d4f3b67422d583c343880493246ab

Using wpt-import in Chromium 561bac59.
With Chromium commits locally applied on WPT:
86af9c78 "Revert "[blinkpy] Re-enable four css-background/ tests that need fuzzy reftest""


Note to sheriffs: This CL imports external tests and adds
expectations for those tests; if this CL is large and causes
a few new failures, please fix the failures by adding new
lines to TestExpectations rather than reverting. See:
https://chromium.googlesource.com/chromium/src/+/master/docs/testing/web_platform_tests.md

NOAUTOREVERT=true
TBR=lpz@google.com

No-Export: true
Cq-Include-Trybots: luci.chromium.try:linux-wpt-identity-fyi-rel,linux-wpt-input-fyi-rel
Change-Id: I648bd7d2a679643b91389e7bccaeb5e31bc557cc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2574679Reviewed-by: WPT Autoroller <wpt-autoroller@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: WPT Autoroller <wpt-autoroller@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#834511}

third_party/blink/web_tests/external/wpt/html/semantics/forms/textfieldselection/selection-start-end.html

@@ -144,6 +144,31 @@
     }
   }, "selectionEnd edge-case values");
 
+  test(() => {
+    for (const el of createTestElements(testValue)) {
+      el.selectionStart = 200;
+      assert_equals(el.selectionStart, testValue.length);
+      el.remove();
+    }
+  }, "selectionStart should be clamped by the current value length");
+
+  test(() => {
+    for (const el of createTestElements(testValue)) {
+      el.selectionStart = 300;
+      assert_equals(el.selectionEnd, testValue.length);
+      el.remove();
+    }
+  }, "selectionEnd should be clamped by the current value length");
+
+  test(() => {
+    for (const el of createTestElements(testValue)) {
+      el.setSelectionRange(200, 300);
+      assert_equals(el.selectionStart, testValue.length);
+      assert_equals(el.selectionEnd, testValue.length);
+      el.remove();
+    }
+  }, "setSelectionRange should be clamped by the current value length");
+
   test(() => {
     for (let el of createTestElements(testValue)) {
       const start = 1;