[wasm] Support asm.js modules with a single function.

src/asmjs/asm-wasm-builder.h

Index: src/asmjs/asm-wasm-builder.h
diff --git a/src/asmjs/asm-wasm-builder.h b/src/asmjs/asm-wasm-builder.h
index 3276c887b0a3d036814028e8cdce98a68a917707..b21e1e35f97ac440ee5dbd2fa8e8ed389cfd7581 100644
--- a/src/asmjs/asm-wasm-builder.h
+++ b/src/asmjs/asm-wasm-builder.h
@@ -24,6 +24,9 @@ class AsmWasmBuilder {
                           AsmTyper* typer);
   ZoneBuffer* Run(Handle<FixedArray>* foreign_args);
 
+  static const char* foreign_init_name;
+  static const char* single_function_name;
+
  private:
   Isolate* isolate_;
   Zone* zone_;