In the current spec, MLGraphBuilder.constant(value, type) allows to build a scalar from the specified number, e.g.,

const a = graphBuilder.constant(42.0, 'float32');

However, MLGraphBuilder.constant(descriptor, bufferView) also allows to build a scalar from data buffer, like the example in #390

const b = graphBuilder.constant({type: 'float32'}, new Float32Array([42.0]));

The proposal is to drop the scalar-specific MLGraphBuilder.constant(value, type) method and only keep more generic MLGraphBuilder.constant(descriptor, bufferView) method.

The scalar-specific build method can be polyfilled by user code. This would help reduce the browser implementation complexity.

/cc @wchao1115 @fdwr @wacky6 @BruceDai @Honry

(Edit by @anssiko: fix link and naming to account for name changes dataType -> type and buffer -> bufferView)