[inspector] always include user scripts in the snapshot.

test/inspector/debugger/step-snapshot.js

Index: test/inspector/debugger/step-snapshot.js
diff --git a/test/inspector/debugger/step-snapshot.js b/test/inspector/debugger/step-snapshot.js
new file mode 100644
index 0000000000000000000000000000000000000000..6e9ee8e7d18b2bf137e2a3f693ffcfe808664028
--- /dev/null
+++ b/test/inspector/debugger/step-snapshot.js
@@ -0,0 +1,30 @@
+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Embed a user function in the snapshot and step through it.
+
+// Flags: --embed 'function c(f, ...args) { return f(...args); }'
+
+InspectorTest.setupScriptMap();
+
+InspectorTest.addScript(`
+function test() {
+  function f(x) {
+    return x * 2;
+  }
+  debugger;
+  c(f, 2);
+}
+//# sourceURL=test.js`);
+
+Protocol.Debugger.onPaused(message => {
+  InspectorTest.log("paused");
+  var frames = message.params.callFrames;
+  InspectorTest.logSourceLocation(frames[0].location);
+  Protocol.Debugger.stepInto();
+})
+
+Protocol.Debugger.enable()
+  .then(() => Protocol.Runtime.evaluate({ expression: 'test()' }))
+  .then(InspectorTest.completeTest);