deno_webgpu: Don't confuse zero with "to the end of the buffer".

`RenderBundleEncoder::set_index_buffer` and `set_vertex_buffer`
interpret a `size` of `None` to mean "from the given offset to the end
of the buffer", but `std::num::NonZeroU64::new` produces `None` when
its argument is zero, which is quite different. Fix this similarly to
the way it's handled in `op_webgpu_render_pass_set_index_buffer`.

The WebGPU spec says this should work; filed as gfx-rs#3170.

deno_webgpu/src/bundle.rs

@@ -1,6 +1,6 @@
 // Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
 
-use deno_core::error::AnyError;
+use deno_core::error::{type_error, AnyError};
 use deno_core::op;
 use deno_core::OpState;
 use deno_core::Resource;
@@ -255,16 +255,14 @@ pub fn op_webgpu_render_bundle_encoder_set_index_buffer(
     let render_bundle_encoder_resource = state
         .resource_table
         .get::<WebGpuRenderBundleEncoder>(render_bundle_encoder_rid)?;
+    let size = Some(
+        std::num::NonZeroU64::new(size).ok_or_else(|| type_error("size must be larger than 0"))?,
+    );
 
     render_bundle_encoder_resource
         .0
         .borrow_mut()
-        .set_index_buffer(
-            buffer_resource.0,
-            index_format,
-            offset,
-            std::num::NonZeroU64::new(size),
-        );
+        .set_index_buffer(buffer_resource.0, index_format, offset, size);
 
     Ok(WebGpuResult::empty())
 }
@@ -284,13 +282,16 @@ pub fn op_webgpu_render_bundle_encoder_set_vertex_buffer(
     let render_bundle_encoder_resource = state
         .resource_table
         .get::<WebGpuRenderBundleEncoder>(render_bundle_encoder_rid)?;
+    let size = Some(
+        std::num::NonZeroU64::new(size).ok_or_else(|| type_error("size must be larger than 0"))?,
+    );
 
     wgpu_core::command::bundle_ffi::wgpu_render_bundle_set_vertex_buffer(
         &mut render_bundle_encoder_resource.0.borrow_mut(),
         slot,
         buffer_resource.0,
         offset,
-        std::num::NonZeroU64::new(size),
+        size,
     );
 
     Ok(WebGpuResult::empty())