Allow implicit zero-init for globals

asm.js

@@ -522,17 +522,13 @@ class Parser {
 
     token_global_init(token) {
         if (token == LINE_END) {
-            console.error(
-                "ERROR: Unexpected newline in .global: expected"
-                    + " initial value");
-            this.global = undefined;
-            this.global_name = undefined;
-            this.state = State.TOP;
+			this.global.init = 0;
         } else {
             const value = this.integer(token) ?? console.error(
                 `ERROR: Unexpected token ${token} in .global: expected`
                     + " initial value");
             this.global.init = value;
+		}
         const action = {
             type: Action.GLOBAL,
             global: { [this.global_name]: this.global }
@@ -542,7 +538,6 @@ class Parser {
         this.state = State.TOP;
         return action;
     }
-    }
 
     token_at_mem(token) {
         this.at = { mem: token };