Fix for HTTPS POST requests with keep-alive failing on OS X versions below 10.10

modules/juce_core/native/juce_mac_Network.mm

@@ -391,6 +391,7 @@ public:
           connection (nil),
           data ([[NSMutableData data] retain]),
           headers (nil),
+          nsUrlErrorCode (0),
           statusCode (0),
           initialised (false),
           hasFailed (false),
@@ -508,6 +509,7 @@ public:
     void didFailWithError (NSError* error)
     {
         DBG (nsStringToJuce ([error description])); ignoreUnused (error);
+        nsUrlErrorCode = [error code];
         hasFailed = true;
         initialised = true;
         signalThreadShouldExit();
@@ -552,6 +554,7 @@ public:
     NSURLConnection* connection;
     NSMutableData* data;
     NSDictionary* headers;
+    NSInteger nsUrlErrorCode;
     int statusCode;
     bool initialised, hasFailed, hasFinished;
     const int numRedirectsToFollow;
@@ -744,7 +747,20 @@ private:
             connection = new URLConnectionState (req, numRedirectsToFollow);
 
             if (! connection->start (progressCallback, progressCallbackContext))
+            {
+                // Workaround for deployment targets below 10.10 where HTTPS POST requests with keep-alive fail with the NSURLErrorNetworkConnectionLost error code
+               #if ! (JUCE_IOS || (defined (__MAC_OS_X_VERSION_MIN_REQUIRED) && defined (__MAC_10_10) && __MAC_OS_X_VERSION_MIN_REQUIRED >= __MAC_10_10))
+                if (connection->nsUrlErrorCode == NSURLErrorNetworkConnectionLost)
+                {
+                    connection = new URLConnectionState (req, numRedirectsToFollow);
+
+                    if (connection->start (progressCallback, progressCallbackContext))
+                        return;
+                }
+               #endif
+
                 connection = nullptr;
+            }
         }
     }