Get url_request_unittest.cc to build on Linux.

base/process_util_linux.cc

 // Copyright (c) 2008 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 "base/process_util.h"
 
 #include <ctype.h>
 #include <dirent.h>
 #include <string>
 #include <sys/types.h>
@@ skipping 22 matching lines @@
 
   char* argv_copy[argv.size() + 1];
   for (size_t i = 0; i < argv.size(); i++) {
     argv_copy[i] = new char[argv[i].size() + 1];
     strcpy(argv_copy[i], argv[i].c_str());
   }
   argv_copy[argv.size()] = NULL;
 
   int pid = fork();
   if (pid == 0) {
-    execv(argv_copy[0], argv_copy);
+    execvp(argv_copy[0], argv_copy);
   } else if (pid < 0) {
     retval = false;
   } else {
     if (wait)
       waitpid(pid, 0, 0);
 
     if(process_handle)
       *process_handle = pid;
   }
 
@@ skipping 262 matching lines @@
           (*io_counters).WriteTransferCount = StringToInt64(tokenizer.token());
         }
         state = KEY_NAME;
         break;
     }
   }
   return true;
 }
 
 }  // namespace process_util