Revert "Proxy webgpu calls back to the main thread. NFC (#20124)" (#21388)

This is a partial revert of 992d1e9

Author: sbc100

src/library_html5_webgpu.js

@@ -90,10 +90,4 @@ var LibraryHTML5WebGPU = {
 {{{ html5_gpu.makeImportExport('render_bundle_encoder', 'RenderBundleEncoder') }}}
 {{{ html5_gpu.makeImportExport('render_bundle', 'RenderBundle') }}}
 
-for (const key of Object.keys(LibraryHTML5WebGPU)) {
-  if (typeof LibraryHTML5WebGPU[key] === 'function' && !(key + '__proxy' in LibraryHTML5WebGPU)) {
-    LibraryHTML5WebGPU[key + '__proxy'] = 'sync';
-  }
-}
-
 addToLibrary(LibraryHTML5WebGPU);

src/library_webgpu.js

@@ -2730,9 +2730,6 @@ for (var value in LibraryWebGPU.$WebGPU.FeatureName) {
 for (const key of Object.keys(LibraryWebGPU)) {
   if (typeof LibraryWebGPU[key] === 'function') {
     LibraryWebGPU[key + '__i53abi'] = true;
-    if (!(key + '__proxy' in LibraryWebGPU)) {
-      LibraryWebGPU[key + '__proxy'] = 'sync';
-    }
   }
 }
 

test/webgpu_get_device.cpp

@@ -1,16 +1,9 @@
-#include <stdio.h>
-
-#include <emscripten/em_asm.h>
+#include <emscripten.h>
 #include <emscripten/html5_webgpu.h>
 
-__attribute__((constructor)) void init() {
+int main() {
   EM_ASM({
     Module['preinitializedWebGPUDevice'] = { this_is: 'a_dummy_object' };
   });
-}
-
-int main() {
-  WGPUDevice d = emscripten_webgpu_get_device();
-  printf("emscripten_webgpu_get_device: %p\n", d);
-  return 0;
+  emscripten_webgpu_get_device();
 }