Adding unit test for two new functions in mime_util.h/cc.

net/base/mime_util_unittest.cc

Index: net/base/mime_util_unittest.cc
diff --git a/net/base/mime_util_unittest.cc b/net/base/mime_util_unittest.cc
index 565f9deeec7e44c2bf540343a7b2955866830065..5b847008d4d17a840665a3a3493af3d692ddd319 100644
--- a/net/base/mime_util_unittest.cc
+++ b/net/base/mime_util_unittest.cc
@@ -296,4 +296,20 @@ TEST(MimeUtilTest, TestGetCertificateMimeTypeForMimeType) {
             GetCertificateMimeTypeForMimeType("text/plain"));
 }
 
+TEST(MimeUtilTest, TestAddMultipartValueForUpload) {
+  const char* ref_output = "--boundary\r\nContent-Disposition: form-data;"
+                           " name=\"value name\"\r\nContent-Type: content type"
+                           "\r\n\r\nvalue\r\n"
+                           "--boundary\r\nContent-Disposition: form-data;"
+                           " name=\"value name\"\r\n\r\nvalue\r\n"
+                           "--boundary--\r\n";
+  std::string post_data;
+  AddMultipartValueForUpload("value name", "value", "boundary",
+                             "content type", &post_data);
+  AddMultipartValueForUpload("value name", "value", "boundary",
+                             "", &post_data);
+  AddMultipartFinalDelimiterForUpload("boundary", &post_data);
+  EXPECT_STREQ(ref_output, post_data.c_str());
+}
+
 }  // namespace net