[wasm][asm.js] Require exported asm.js functions have be names.

src/asmjs/asm-typer.cc

Index: src/asmjs/asm-typer.cc
diff --git a/src/asmjs/asm-typer.cc b/src/asmjs/asm-typer.cc
index a05422ffd3492814925f7574c2ee6e9738ae0a32..dff43b7db61bf4c402a2dfd3fd774cfb11c8641c 100644
--- a/src/asmjs/asm-typer.cc
+++ b/src/asmjs/asm-typer.cc
@@ -935,6 +935,10 @@ AsmType* AsmTyper::ValidateExport(ReturnStatement* exports) {
              "Only normal object properties may be used in the export object "
              "literal.");
       }
+      if (!prop->key()->AsLiteral()->IsPropertyName()) {
+        FAIL(prop->key(),
+             "Exported functions must have valid identifier names.");
+      }
 
       auto* export_obj = prop->value()->AsVariableProxy();
       if (export_obj == nullptr) {