WebUI: Fix compile_js2.py to retrigger compilation for <include> files.

third_party/closure_compiler/build/get_includes.py

Index: third_party/closure_compiler/build/get_includes.py
diff --git a/third_party/closure_compiler/build/get_includes.py b/third_party/closure_compiler/build/get_includes.py
new file mode 100755
index 0000000000000000000000000000000000000000..6d976dbb88a74448d73568faf06f1eeb964adf45
--- /dev/null
+++ b/third_party/closure_compiler/build/get_includes.py
@@ -0,0 +1,24 @@
+#!/usr/bin/python
+# Copyright 2017 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import os.path
+import sys
+
+
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
+import processor
+
+
+def GetIncludes(inputs):
+  includes = set()
+  for f in inputs:
+    includes.update(processor.Processor(f).included_files)
+  return includes
+
+
+if __name__ == "__main__":
+  # TODO(dpapad): Dedup inputs in ninja files, using relative paths with respect
+  # to the out directory.
+  print "\n".join(GetIncludes(sys.argv[1:]))