Move the FileAPI directory from web-platform-tests/ to wpt/.

third_party/WebKit/LayoutTests/imported/wpt/FileAPI/support/Blob.js

 function test_blob(fn, expectations) {
   var expected = expectations.expected,
       type = expectations.type,
       desc = expectations.desc;
 
   var t = async_test(desc);
   t.step(function() {
     var blob = fn();
     assert_true(blob instanceof Blob);
     assert_false(blob instanceof File);
@@ skipping 29 matching lines @@
       assert_true(this.result instanceof ArrayBuffer,
                   "Result should be an ArrayBuffer");
       assert_array_equals(new Uint8Array(this.result), expected);
     }, fr);
     fr.onerror = t.step_func(function(e) {
       assert_unreached("got error event on FileReader");
     });
     fr.readAsArrayBuffer(blob);
   });
 }