Add @requires_es6_workers decorator (#25420)

Add @requires_es6_workers decorator for flagging tests that depend on
ES6 Module Workers support

Author: juj

test/test_browser.py

@@ -203,6 +203,7 @@ def webgpu_disabled():
 requires_webgpu = unittest.skipIf(webgpu_disabled(), "This test requires WebGPU to be available")
 requires_sound_hardware = skipExecIf(os.getenv('EMTEST_LACKS_SOUND_HARDWARE'), 'This test requires sound hardware')
 requires_offscreen_canvas = skipExecIf(os.getenv('EMTEST_LACKS_OFFSCREEN_CANVAS'), 'This test requires a browser with OffscreenCanvas')
+requires_es6_workers = skipExecIf(os.getenv('EMTEST_LACKS_ES6_WORKERS'), 'This test requires a browser with ES6 Module Workers support')
 
 
 class browser(BrowserCore):
@@ -4732,6 +4733,7 @@ def test_pthread_reltime(self):
     'blob_es6': (True, True),
     'url_es6': (True, False),
   })
+  @requires_es6_workers
   def test_mainScriptUrlOrBlob(self, es6, use_blob):
     # TODO: enable this with wasm, currently pthreads/atomics have limitations
     self.set_setting('EXIT_RUNTIME')
@@ -5081,6 +5083,7 @@ def test_system(self):
   def test_wasm_worker_hello(self):
     self.btest_exit('wasm_worker/hello_wasm_worker.c', cflags=['-sWASM_WORKERS', '-sENVIRONMENT=web'])
 
+  @requires_es6_workers
   def test_wasm_worker_hello_export_es6(self):
     self.btest_exit('wasm_worker/hello_wasm_worker.c', cflags=['-sWASM_WORKERS', '-sENVIRONMENT=web', '-sEXPORT_ES6'])
 
@@ -5474,6 +5477,7 @@ def test_full_js_library_strict(self):
     'audio_params_disabled': (['-sAUDIO_WORKLET_SUPPORT_AUDIO_PARAMS=0'],),
   })
   @requires_sound_hardware
+  @requires_es6_workers
   def test_audio_worklet(self, args):
     self.btest_exit('webaudio/audioworklet.c', cflags=['-sAUDIO_WORKLET', '-sWASM_WORKERS', '-DTEST_AND_EXIT'] + args)