Add tests for paint-timing, and move existing tests to same location

third_party/WebKit/LayoutTests/http/tests/performance-timing/paint-timing/first-paint-only.html

Index: third_party/WebKit/LayoutTests/http/tests/performance-timing/paint-timing/first-paint-only.html
diff --git a/third_party/WebKit/LayoutTests/fast/performance/performance-first-paint-timing-observable.html b/third_party/WebKit/LayoutTests/http/tests/performance-timing/paint-timing/first-paint-only.html
similarity index 88%
rename from third_party/WebKit/LayoutTests/fast/performance/performance-first-paint-timing-observable.html
rename to third_party/WebKit/LayoutTests/http/tests/performance-timing/paint-timing/first-paint-only.html
index 081aeb32005712254a85941fab742c9930d854c4..c427faa03843fa456b56eb75465f05638f377ad9 100644
--- a/third_party/WebKit/LayoutTests/fast/performance/performance-first-paint-timing-observable.html
+++ b/third_party/WebKit/LayoutTests/http/tests/performance-timing/paint-timing/first-paint-only.html
@@ -21,14 +21,14 @@
                 assert_equals(entries[0].duration, 0,
                     "Expected duration to be: 0.");
                 observer.disconnect();
-                t.done();
             })
         );
         observer.observe({entryTypes: ["paint"]});
 
-    }, "Performance first paint timing entry is observable.");
+        t.step_timeout(function() { t.done(); }, 1000);
+    }, "Performance first paint timing entry is observable. No first contentful paint.");
     </script>
-    
+
     <div style="background-color:black;color:white;padding:20px;"></div>
 </body>
 </html>