Permit non-struct, non-array types as buffers.

Fixes #2583.

wgpu-core/src/validation.rs

@@ -868,9 +868,6 @@ impl Interface {
                 _ => continue,
             };
             let ty = match module.types[var.ty].inner {
-                naga::TypeInner::Struct { members: _, span } => ResourceType::Buffer {
-                    size: wgt::BufferSize::new(span as u64).unwrap(),
-                },
                 naga::TypeInner::Image {
                     dim,
                     arrayed,
@@ -884,10 +881,9 @@ impl Interface {
                 naga::TypeInner::Array { stride, .. } => ResourceType::Buffer {
                     size: wgt::BufferSize::new(stride as u64).unwrap(),
                 },
-                ref other => {
-                    log::error!("Unexpected resource type: {:?}", other);
-                    continue;
-                }
+                ref other => ResourceType::Buffer {
+                    size: wgt::BufferSize::new(other.size(&module.constants) as u64).unwrap(),
+                },
             };
             let handle = resources.append(
                 Resource {

wgpu/examples/cube/shader.wgsl

@@ -3,12 +3,9 @@ struct VertexOutput {
     @builtin(position) position: vec4<f32>,
 };
 
-struct Locals {
-    transform: mat4x4<f32>
-};
 @group(0)
 @binding(0)
-var<uniform> r_locals: Locals;
+var<uniform> transform: mat4x4<f32>;
 
 @vertex
 fn vs_main(
@@ -17,7 +14,7 @@ fn vs_main(
 ) -> VertexOutput {
     var result: VertexOutput;
     result.tex_coord = tex_coord;
-    result.position = r_locals.transform * position;
+    result.position = transform * position;
     return result;
 }