Worklet: Straighten layering of worklet script loading

third_party/WebKit/LayoutTests/http/tests/worklet/resources/import-tests.js

 // Runs a series of tests related to importing scripts on a worklet.
 //
 // Usage:
 // runImportTests(workletType);
 function runImportTests(worklet, opt_path) {
     const path = opt_path || '';
 
     promise_test(function() {
         return worklet.import(path + 'resources/empty-worklet-script.js').then(function(undefined_arg) {
             assert_equals(undefined_arg, undefined, 'Promise should resolve with no arguments.');
-        }).catch(function(error) {
-            assert_unreached('unexpected rejection: ' + error);
         });
-
     }, 'Importing a script resolves the given promise.');
 
     promise_test(function() {
+        return Promise.all([
+            worklet.import(path + 'resources/empty-worklet-script.js?1'),
+            worklet.import(path + 'resources/empty-worklet-script.js?2'),
+            worklet.import(path + 'resources/empty-worklet-script.js?3')
+        ]).then(function(undefined_args) {
+            assert_array_equals(undefined_args, [undefined, undefined, undefined], 'Promise should resolve with no arguments.');
+        });
+    }, 'Importing scripts resolves all the given promises.');
 
+    promise_test(function() {
         return worklet.import(path + 'resources/throwing-worklet-script.js').then(function(undefined_arg) {
             assert_equals(undefined_arg, undefined, 'Promise should resolve with no arguments.');
-        }).catch(function(error) {
-            assert_unreached('unexpected rejection: ' + error);
         });
-
     }, 'Importing a script which throws should still resolve the given promise.');
 
     promise_test(function() {
-
         return worklet.import(path + 'non-existant-worklet-script.js').then(function() {
             assert_unreached('import should fail.');
         }).catch(function(error) {
             assert_equals(error.name, 'NetworkError', 'error should be a NetworkError.');
         });
-
     }, 'Importing a non-existant script rejects the given promise with a NetworkError.');
 
     promise_test(function() {
-
         return worklet.import('http://invalid:123$').then(function() {
             assert_unreached('import should fail.');
         }).catch(function(error) {
             assert_equals(error.name, 'SyntaxError', 'error should be a SyntaxError.');
         });
-
     }, 'Attempting to resolve an invalid URL should reject the given promise with a SyntaxError.');
 }