Support GCC 4.7

Removed constructors inheritance.
Removed emplace use.

Change-Id: I45224e3232d39ff22f758c7e387be2c9aff5eae0
Reviewed-on: https://weave-review.googlesource.com/1606
Reviewed-by: Vitaly Buka <vitalybuka@google.com>
diff --git a/src/notification/xmpp_iq_stanza_handler.cc b/src/notification/xmpp_iq_stanza_handler.cc
index 8753030..9ac4223 100644
--- a/src/notification/xmpp_iq_stanza_handler.cc
+++ b/src/notification/xmpp_iq_stanza_handler.cc
@@ -72,7 +72,7 @@
     const ResponseCallback& response_callback,
     const TimeoutCallback& timeout_callback) {
   // Remember the response callback to call later.
-  requests_.emplace(++last_request_id_, response_callback);
+  requests_.insert(std::make_pair(++last_request_id_, response_callback));
   // Schedule a time-out callback for this request.
   if (timeout < base::TimeDelta::Max()) {
     task_runner_->PostDelayedTask(
diff --git a/src/notification/xmpp_stream_parser.cc b/src/notification/xmpp_stream_parser.cc
index de3b8f1..9efaeb5 100644
--- a/src/notification/xmpp_stream_parser.cc
+++ b/src/notification/xmpp_stream_parser.cc
@@ -36,7 +36,7 @@
   std::map<std::string, std::string> attributes;
   if (attr != nullptr) {
     for (size_t n = 0; attr[n] != nullptr && attr[n + 1] != nullptr; n += 2) {
-      attributes.emplace(attr[n], attr[n + 1]);
+      attributes.insert(std::make_pair(attr[n], attr[n + 1]));
     }
   }
   self->OnOpenElement(element, std::move(attributes));