Fix Closure Compiler's compile.py error checking

third_party/closure_compiler/compile2.py

 #!/usr/bin/python
 # Copyright 2015 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.
 
 """Runs Closure compiler on JavaScript files to check for errors and produce
 minified output."""
 
 import argparse
 import os
@@ skipping 248 matching lines @@
       args += ["--create_source_map=%s" % (self._MAP_FILE_FORMAT % out_file)]
 
     args_file_content = " %s" % " ".join(args)
     self._log_debug("Args: %s" % args_file_content.strip())
 
     args_file = self._create_temp_file(args_file_content)
     self._log_debug("Args file: %s" % args_file)
 
     processed_runner_args = ["--%s" % arg for arg in runner_args or []]
     processed_runner_args += ["--compiler-args-file=%s" % args_file]
-    _, stderr = self._run_jar(self._runner_jar, processed_runner_args)
+    return_code, stderr = self._run_jar(self._runner_jar, processed_runner_args)
 
     errors = stderr.strip().split("\n\n")
     maybe_summary = errors.pop()
 
-    summary = re.search("(?P<error_count>\d+).*error.*warning", maybe_summary)
-    if summary:
+    if return_code == 0:
       self._log_debug("Summary: %s" % maybe_summary)
     else:
-      # Not a summary. Running the jar failed. Bail.
+      # Running the jar failed.
       self._log_error(stderr)
       self._nuke_temp_files()
-      sys.exit(1)
 
+    summary = re.search("(?P<error_count>\d+).*error.*warning", maybe_summary)
     if summary.group('error_count') != "0" and out_file:
       if os.path.exists(out_file):
         os.remove(out_file)
       if os.path.exists(self._MAP_FILE_FORMAT % out_file):
         os.remove(self._MAP_FILE_FORMAT % out_file)
 
     if not custom_sources:
       filtered_errors = self._filter_errors(errors)
       errors = map(self._clean_up_error, filtered_errors)
       output = self._format_errors(errors)
@@ skipping 29 matching lines @@
 
   found_errors, stderr = checker.check(opts.sources, out_file=opts.out_file,
                                        closure_args=opts.closure_args,
                                        runner_args=opts.runner_args,
                                        custom_sources=opts.custom_sources)
 
   if found_errors:
     if opts.custom_sources:
       print stderr
     sys.exit(1)