Improve map insertions

util/net/http_transport_test.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 204 matching lines @@
   ASSERT_EQ(body_start + expected.length(), request.length());
   EXPECT_EQ(expected, request.substr(body_start));
 }
 
 TEST(HTTPTransport, ValidFormData) {
   HTTPMultipartBuilder builder;
   builder.SetFormData("key1", "test");
   builder.SetFormData("key2", "--abcdefg123");
 
   HTTPHeaders headers;
-  headers.insert(builder.GetContentType());
+  EXPECT_TRUE(headers.insert(builder.GetContentType()).second);
 
   HTTPTransportTestFixture test(headers, builder.GetBodyStream(), 200,
       &ValidFormData);
   test.Run();
 }
 
 const char kTextPlain[] = "text/plain";
 
 void ErrorResponse(HTTPTransportTestFixture* fixture,
                    const std::string& request) {
@@ skipping 38 matching lines @@
   headers[kContentLength] = base::StringPrintf("%" PRIuS, strlen(kTextBody));
 
   HTTPTransportTestFixture test(headers, body_stream.Pass(), 200,
       &UnchunkedPlainText);
   test.Run();
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace crashpad