Make sure that HttpRequestHeaders contains valid key-value pairs.

net/http/http_request_headers.cc

Index: net/http/http_request_headers.cc
diff --git a/net/http/http_request_headers.cc b/net/http/http_request_headers.cc
index 9348e3e27788ad7e1d82ec478ecc54482b147950..f0b7cfb6d1f8f6b42043f3e0aa0c67e083ef5f26 100644
--- a/net/http/http_request_headers.cc
+++ b/net/http/http_request_headers.cc
@@ -84,6 +84,8 @@ void HttpRequestHeaders::Clear() {
 
 void HttpRequestHeaders::SetHeader(const base::StringPiece& key,
                                    const base::StringPiece& value) {
+  DCHECK(HttpUtil::IsValidHeaderName(key.as_string()));
+  DCHECK(HttpUtil::IsValidHeaderValue(value.as_string()));
   HeaderVector::iterator it = FindHeader(key);
   if (it != headers_.end())
     it->value.assign(value.data(), value.size());
@@ -93,6 +95,8 @@ void HttpRequestHeaders::SetHeader(const base::StringPiece& key,
 
 void HttpRequestHeaders::SetHeaderIfMissing(const base::StringPiece& key,
                                             const base::StringPiece& value) {
+  DCHECK(HttpUtil::IsValidHeaderName(key.as_string()));
+  DCHECK(HttpUtil::IsValidHeaderValue(value.as_string()));
   HeaderVector::iterator it = FindHeader(key);
   if (it == headers_.end())
     headers_.push_back(HeaderKeyValuePair(key, value));