Port "Eclipse CDT settings" file generation from GYP to GN

tools/gn/xml_element_writer_unittest.cc

 // Copyright 2016 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.
 
 #include "tools/gn/xml_element_writer.h"
 
 #include <sstream>
 
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
 class MockValueWriter {
  public:
   explicit MockValueWriter(const std::string& value) : value_(value) {}
   void operator()(std::ostream& out) const { out << value_; }
 
  private:
   std::string value_;
 };
 
 }  // namespace
 
 TEST(XmlElementWriter, EmptyElement) {
   std::ostringstream out;
   { XmlElementWriter writer(out, "foo", XmlAttributes()); }
-  EXPECT_EQ("<foo/>\n", out.str());
+  EXPECT_EQ("<foo />\n", out.str());
 
   std::ostringstream out_attr;
   {
     XmlElementWriter writer(out_attr, "foo",
                             XmlAttributes("bar", "abc").add("baz", "123"));
   }
-  EXPECT_EQ("<foo bar=\"abc\" baz=\"123\"/>\n", out_attr.str());
+  EXPECT_EQ("<foo bar=\"abc\" baz=\"123\" />\n", out_attr.str());
 
   std::ostringstream out_indent;
   {
     XmlElementWriter writer(out_indent, "foo", XmlAttributes("bar", "baz"), 2);
   }
-  EXPECT_EQ("  <foo bar=\"baz\"/>\n", out_indent.str());
+  EXPECT_EQ("  <foo bar=\"baz\" />\n", out_indent.str());
 
   std::ostringstream out_writer;
   {
     XmlElementWriter writer(out_writer, "foo", "bar", MockValueWriter("baz"),
                             2);
   }
-  EXPECT_EQ("  <foo bar=\"baz\"/>\n", out_writer.str());
+  EXPECT_EQ("  <foo bar=\"baz\" />\n", out_writer.str());
 }
 
 TEST(XmlElementWriter, ElementWithText) {
   std::ostringstream out;
   {
     XmlElementWriter writer(out, "foo", XmlAttributes("bar", "baz"));
     writer.Text("Hello world!");
   }
   EXPECT_EQ("<foo bar=\"baz\">Hello world!</foo>\n", out.str());
 }
 
 TEST(XmlElementWriter, SubElements) {
   std::ostringstream out;
   {
     XmlElementWriter writer(out, "root", XmlAttributes("aaa", "000"));
     writer.SubElement("foo", XmlAttributes());
     writer.SubElement("bar", XmlAttributes("bbb", "111"))->Text("hello");
     writer.SubElement("baz", "ccc", MockValueWriter("222"))
         ->SubElement("grandchild");
   }
   std::string expected =
       "<root aaa=\"000\">\n"
-      "  <foo/>\n"
+      "  <foo />\n"
       "  <bar bbb=\"111\">hello</bar>\n"
       "  <baz ccc=\"222\">\n"
-      "    <grandchild/>\n"
+      "    <grandchild />\n"
       "  </baz>\n"
       "</root>\n";
   EXPECT_EQ(expected, out.str());
 }
 
 TEST(XmlElementWriter, StartContent) {
   std::ostringstream out;
   {
     XmlElementWriter writer(out, "foo", XmlAttributes("bar", "baz"));
     writer.StartContent(false) << "Hello world!";
   }
   EXPECT_EQ("<foo bar=\"baz\">Hello world!</foo>\n", out.str());
 }