[vmbase] Check layout not empty during memory allocation

Bug: 291586508
Test: atest rialo_test
Change-Id: I0dbe1e53ad026cd6bd2185b02f21dcfa126efc3a
diff --git a/vmbase/src/memory/shared.rs b/vmbase/src/memory/shared.rs
index f4c9f72..dfa29e4 100644
--- a/vmbase/src/memory/shared.rs
+++ b/vmbase/src/memory/shared.rs
@@ -341,11 +341,7 @@
 /// Allocates a memory range of at least the given size and alignment that is shared with the host.
 /// Returns a pointer to the buffer.
 pub(crate) fn alloc_shared(layout: Layout) -> hyp::Result<NonNull<u8>> {
-    // TODO(b/291586508): We have temporarily removed the non-zero check for layout.size() to
-    // enable the Rialto socket device to connect or shut down, as the socket driver adds empty
-    // buffers in these scenarios.
-    // We will add the check back once this issue is fixed in the driver.
-
+    assert_ne!(layout.size(), 0);
     let Some(buffer) = try_shared_alloc(layout) else {
         handle_alloc_error(layout);
     };