Emscripten: Add support for GPUAdapterInfo isFallbackAdapter

Bug: 403172841
Change-Id: I09b3a061e4137b53bddfdc531d514ac3ea5219c3
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/232074
Reviewed-by: Loko Kung <lokokung@google.com>
Commit-Queue: Fr <beaufort.francois@gmail.com>

third_party/emdawnwebgpu/library_webgpu.js

diff --git a/third_party/emdawnwebgpu/library_webgpu.js b/third_party/emdawnwebgpu/library_webgpu.js
index 44d5457..a121f57 100644
--- a/third_party/emdawnwebgpu/library_webgpu.js
+++ b/third_party/emdawnwebgpu/library_webgpu.js
@@ -729,7 +729,7 @@
     strPtr += descriptionLen;
 
     {{{ makeSetValue('info', C_STRUCTS.WGPUAdapterInfo.backendType, gpu.BackendType.WebGPU, 'i32') }}};
-    var adapterType = adapter.isFallbackAdapter ? {{{ gpu.AdapterType.CPU }}} : {{{ gpu.AdapterType.Unknown }}};
+    var adapterType = adapter.info.isFallbackAdapter ? {{{ gpu.AdapterType.CPU }}} : {{{ gpu.AdapterType.Unknown }}};
     {{{ makeSetValue('info', C_STRUCTS.WGPUAdapterInfo.adapterType, 'adapterType', 'i32') }}};
     {{{ makeSetValue('info', C_STRUCTS.WGPUAdapterInfo.vendorID, '0', 'i32') }}};
     {{{ makeSetValue('info', C_STRUCTS.WGPUAdapterInfo.deviceID, '0', 'i32') }}};
@@ -1851,8 +1851,7 @@
     strPtr += descriptionLen;
 
     {{{ makeSetValue('adapterInfo', C_STRUCTS.WGPUAdapterInfo.backendType, gpu.BackendType.WebGPU, 'i32') }}};
-    // TODO: Set the adapter type from adapter.isFallbackAdapter (not easily available here).
-    var adapterType = {{{ gpu.AdapterType.Unknown }}};
+    var adapterType = device.adapterInfo.isFallbackAdapter ? {{{ gpu.AdapterType.CPU }}} : {{{ gpu.AdapterType.Unknown }}};
     {{{ makeSetValue('adapterInfo', C_STRUCTS.WGPUAdapterInfo.adapterType, 'adapterType', 'i32') }}};
     {{{ makeSetValue('adapterInfo', C_STRUCTS.WGPUAdapterInfo.vendorID, '0', 'i32') }}};
     {{{ makeSetValue('adapterInfo', C_STRUCTS.WGPUAdapterInfo.deviceID, '0', 'i32') }}};