accept more performance mark name and return dummy 0

src/browser/tests/performance.html

@@ -252,6 +252,28 @@
   }
 </script>
 
+<script id=measure_with_navigation_timing_marks>
+  {
+    // performance.measure() must accept PerformanceTiming attribute names
+    // (e.g. "fetchStart") as start/end marks per the W3C User Timing Level 2 spec.
+    // https://www.w3.org/TR/user-timing/#dom-performance-measure
+    performance.clearMarks();
+    performance.clearMeasures();
+
+    performance.mark("mark-dataComplete");
+    let m = performance.measure("dataComplete", "fetchStart", "mark-dataComplete");
+    testing.expectEqual('dataComplete', m.name);
+    testing.expectEqual('measure', m.entryType);
+    testing.expectEqual(true, m.duration >= 0);
+
+    // navigationStart is also a valid mark name (was already supported)
+    performance.mark("mark-end");
+    let m2 = performance.measure("fromNav", "navigationStart", "mark-end");
+    testing.expectEqual('fromNav', m2.name);
+    testing.expectEqual(true, m2.duration >= 0);
+  }
+</script>
+
 <script id=mixed_marks_and_measures>
   {
     performance.clearMarks();

src/browser/webapi/Performance.zig

@@ -208,11 +208,41 @@ fn getMarkTime(self: *const Performance, mark_name: []const u8) !f64 {
         }
     }
 
-    // Recognized mark names by browsers. `navigationStart` is an equivalent
+    // PerformanceTiming attribute names are valid start/end marks per the
-    // to 0. Others are dependant to request arrival, end of request etc.
+    // W3C User Timing Level 2 spec. All are relative to navigationStart (= 0).
-    if (std.mem.eql(u8, "navigationStart", mark_name)) {
+    // https://www.w3.org/TR/user-timing/#dom-performance-measure
+    //
+    // `navigationStart` is an equivalent to 0.
+    // Others are dependant to request arrival, end of request etc, but we
+    // return a dummy 0 value for now.
+    const navigation_timing_marks = [_][]const u8{
+        "navigationStart",
+        "unloadEventStart",
+        "unloadEventEnd",
+        "redirectStart",
+        "redirectEnd",
+        "fetchStart",
+        "domainLookupStart",
+        "domainLookupEnd",
+        "connectStart",
+        "connectEnd",
+        "secureConnectionStart",
+        "requestStart",
+        "responseStart",
+        "responseEnd",
+        "domLoading",
+        "domInteractive",
+        "domContentLoadedEventStart",
+        "domContentLoadedEventEnd",
+        "domComplete",
+        "loadEventStart",
+        "loadEventEnd",
+    };
+    for (navigation_timing_marks) |name| {
+        if (std.mem.eql(u8, name, mark_name)) {
             return 0;
         }
+    }
 
     return error.SyntaxError; // Mark not found
 }