Move web-platform-tests to wpt (part 1 of 2)

third_party/WebKit/LayoutTests/imported/web-platform-tests/hr-time/basic.worker.js

-importScripts("/resources/testharness.js");
-
-test(function() {
-  assert_true((performance !== undefined), "WorkerGlobalScope.performance exists");
-  assert_equals((typeof performance.now), "function");
-}, "WorkerGlobalScope.performance.now() is a function");
-
-test(function() {
-  assert_true(performance.now() > 0);
-}, "WorkerGlobalScope.performance.now() returns a positive number");
-
-test(function() {
-    var now1 = performance.now();
-    var now2 = performance.now();
-    assert_true((now2-now1) >= 0);
-  }, "WorkerGlobalScope.performance.now() difference is not negative");
-
-done();