Stop using third_party\python_26 for many tests.

net/test/python_utils.cc

Index: net/test/python_utils.cc
diff --git a/net/test/python_utils.cc b/net/test/python_utils.cc
index bf66bea93bd2e79ce2bb5ea2a4244e5bd83b3909..e249a27f27a4d0b8c32ece8799e44f28453bd7cd 100644
--- a/net/test/python_utils.cc
+++ b/net/test/python_utils.cc
@@ -109,8 +109,14 @@ bool GetPyProtoPath(base::FilePath* dir) {
 bool GetPythonCommand(CommandLine* python_cmd) {
   DCHECK(python_cmd);
 
+#if defined(OS_WIN)
+  // This permits finding the proper python in path even if it is a .bat file.
+  python_cmd->SetProgram(base::FilePath(FILE_PATH_LITERAL("cmd.exe")));
+  python_cmd->AppendArg("/c");
+  python_cmd->AppendArg("python");
+#else
   python_cmd->SetProgram(base::FilePath(FILE_PATH_LITERAL("python")));
-
+#endif  // defined(OS_WIN)
   // Launch python in unbuffered mode, so that python output doesn't mix with
   // gtest output in buildbot log files. See http://crbug.com/147368.
   python_cmd->AppendArg("-u");