AU: Set connection timeout to 30 seconds.

libcurl_http_fetcher.cc

Index: libcurl_http_fetcher.cc
diff --git a/libcurl_http_fetcher.cc b/libcurl_http_fetcher.cc
index af7e8453a32fa7227be60ff928e2b97d25875b50..eb9d7d8923fc6f7cc441c1004eba67ea6fb92993 100644
--- a/libcurl_http_fetcher.cc
+++ b/libcurl_http_fetcher.cc
@@ -122,6 +122,8 @@ void LibcurlHttpFetcher::ResumeTransfer(const std::string& url) {
   const int kTimeout = IsOfficialBuild() ? 90 : 3 * 60;
   CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_LOW_SPEED_TIME, kTimeout),
            CURLE_OK);
+  CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_CONNECTTIMEOUT, 30),
+           CURLE_OK);
 
   // By default, libcurl doesn't follow redirections. Allow up to
   // |kMaxRedirects| redirections.