style(3p/nix): Reformat project in Google C++ style

Reformatted with:

    fd . -e hh -e cc | xargs clang-format -i

third_party/nix/src/libutil/xml-writer.hh

@@ -1,69 +1,56 @@
 #pragma once
 
 #include <iostream>
-#include <string>
 #include <list>
 #include <map>
-
+#include <string>
 
 namespace nix {
 
-using std::string;
-using std::map;
 using std::list;
-
+using std::map;
+using std::string;
 
 typedef map<string, string> XMLAttrs;
 
+class XMLWriter {
+ private:
+  std::ostream& output;
 
-class XMLWriter
-{
-private:
+  bool indent;
+  bool closed;
 
-    std::ostream & output;
+  list<string> pendingElems;
 
-    bool indent;
-    bool closed;
+ public:
+  XMLWriter(bool indent, std::ostream& output);
+  ~XMLWriter();
 
-    list<string> pendingElems;
+  void close();
 
-public:
+  void openElement(const string& name, const XMLAttrs& attrs = XMLAttrs());
+  void closeElement();
 
-    XMLWriter(bool indent, std::ostream & output);
-    ~XMLWriter();
+  void writeEmptyElement(const string& name,
+                         const XMLAttrs& attrs = XMLAttrs());
 
-    void close();
+ private:
+  void writeAttrs(const XMLAttrs& attrs);
 
-    void openElement(const string & name,
-        const XMLAttrs & attrs = XMLAttrs());
-    void closeElement();
-
-    void writeEmptyElement(const string & name,
-        const XMLAttrs & attrs = XMLAttrs());
-
-private:
-    void writeAttrs(const XMLAttrs & attrs);
-
-    void indent_(size_t depth);
+  void indent_(size_t depth);
 };
 
+class XMLOpenElement {
+ private:
+  XMLWriter& writer;
 
-class XMLOpenElement
-{
-private:
-    XMLWriter & writer;
-public:
-    XMLOpenElement(XMLWriter & writer, const string & name,
-        const XMLAttrs & attrs = XMLAttrs())
-        : writer(writer)
-    {
-        writer.openElement(name, attrs);
-    }
-    ~XMLOpenElement()
-    {
-        writer.closeElement();
-    }
+ public:
+  XMLOpenElement(XMLWriter& writer, const string& name,
+                 const XMLAttrs& attrs = XMLAttrs())
+      : writer(writer) {
+    writer.openElement(name, attrs);
+  }
+  ~XMLOpenElement() { writer.closeElement(); }
 };
 
-
-}
+}  // namespace nix