fix corner case in inline (#5402)

fixes #5401

lib/compress.js

@@ -13508,6 +13508,12 @@ Compressor.prototype.compress = function(node) {
         def(AST_LabeledStatement, function(compressor, scope, no_return, in_loop) {
             var body = this.body.try_inline(compressor, scope, no_return, in_loop);
             if (!body) return;
+            if (this.body instanceof AST_IterationStatement && body instanceof AST_BlockStatement) {
+                var loop = body.body.pop();
+                this.body = loop;
+                body.body.push(this);
+                return body;
+            }
             this.body = body;
             return this;
         });

test/compress/functions.js

@@ -8350,3 +8350,23 @@ issue_5376_2: {
     }
     expect_stdout: Error("PASS")
 }
+
+issue_5401: {
+    options = {
+        inline: true,
+    }
+    input: {
+        L: for (var a in function() {
+            while (console.log("PASS"));
+        }(), a) do {
+            continue L;
+        } while (console.log("FAIL"));
+    }
+    expect: {
+        while (console.log("PASS"));
+        L: for (var a in a) do {
+            continue L;
+        } while (console.log("FAIL"));
+    }
+    expect_stdout: "PASS"
+}