message: Convert XLA shape to static before converting it to MemRefType
  This is in preparation to fail xla::ConvertShapeToType for dynamic shapes
  instead of silently converting it to MemRefType using bounds as dimension
  sizes.
diff: @@ -1558,8 +1558,11 @@ Status LhloDialectEmitter::Initialize() {
  ->shape(),
  alloc->param_shape_index());
  + // TODO(jurahul): Revisit this when we can model memrefs with dynamic
  + // shape but static bounds in MLIR.
  + const Shape static_shape = xla::ShapeUtil::MakeStaticShape(buffer_shape);
  TF_ASSIGN_OR_RETURN(auto arg_type, xla::ConvertShapeToType<MemRefType>(
  - buffer_shape, builder_));
  + static_shape, builder_));
  // First map parameters to memrefs on the operation.
  block->addArgument(arg_type);
  