| Index: tools/gn/filesystem_utils.cc
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| diff --git a/tools/gn/filesystem_utils.cc b/tools/gn/filesystem_utils.cc
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| index 42736c9fbfa690b74f18fc088d6b013351adac27..663e6ac3f0c188d708a366d3326eb273605d4130 100644
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| --- a/tools/gn/filesystem_utils.cc
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| +++ b/tools/gn/filesystem_utils.cc
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| @@ -748,7 +748,8 @@ OutputFile GetOutputDirForSourceDirAsOutputFile(const Settings* settings,
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|      const std::string& build_dir =
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|          settings->build_settings()->build_dir().value();
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|  
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| -    if (base::StartsWithASCII(source_dir.value(), build_dir, true)) {
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| +    if (base::StartsWith(source_dir.value(), build_dir,
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| +                         base::CompareCase::SENSITIVE)) {
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|        size_t build_dir_size = build_dir.size();
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|        result.value().append(&source_dir.value()[build_dir_size],
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|                              source_dir.value().size() - build_dir_size);
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| 
 |