Made TimeZone string generation locale-agnostic for Windows Phone and Unity.

Previously, TimeZone string generation that we sent along with
ParseInstallation was dependent upon the CurrentCulture of the device
being set to the english locale (as StandardName is localized, WHAT?!)

Our new, fancy TimeZone string is now generated agnostically of the
current device locale. There is potential for information about the
specific region of the time zone to be lost here, but most applications
should not require this.

This should fix #138.

Author: richardjrossiii

Parse/Internal/PlatformHooks/Phone/PlatformHooks.Phone.cs

@@ -150,17 +150,12 @@ public string DeviceType {
 
     public string DeviceTimeZone {
       get {
-        // We need the system string to be in english so we'll have the proper key in our lookup table.
-        var culture = Thread.CurrentThread.CurrentCulture;
-        Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
-        string windowsName = TimeZoneInfo.Local.StandardName;
-        Thread.CurrentThread.CurrentCulture = culture;
-
-        if (ParseInstallation.TimeZoneNameMap.ContainsKey(windowsName)) {
-          return ParseInstallation.TimeZoneNameMap[windowsName];
-        } else {
-          return null;
-        }
+        TimeSpan utcOffset = TimeZoneInfo.Local.BaseUtcOffset;
+        return String.Format("GMT{0}{1}:{2:d2}",
+          offset.TotalSeconds < 0 ? "-" : "+",
+          Math.Abs(offset.Hours),
+          Math.Abs(offset.Minutes)
+        );
       }
     }
 

Parse/Internal/PlatformHooks/Unity/PlatformHooks.Unity.cs

@@ -87,16 +87,12 @@ public string DeviceType {
 
     public string DeviceTimeZone {
       get {
-        try {
-          string windowsName = TimeZoneInfo.Local.StandardName;
-          if (ParseInstallation.TimeZoneNameMap.ContainsKey(windowsName)) {
-            return ParseInstallation.TimeZoneNameMap[windowsName];
-          } else {
-            return null;
-          }
-        } catch (TimeZoneNotFoundException) {
-          return null;
-        }
+        TimeSpan utcOffset = TimeZoneInfo.Local.BaseUtcOffset;
+        return String.Format("GMT{0}{1}:{2:d2}",
+          offset.TotalSeconds < 0 ? "-" : "+",
+          Math.Abs(offset.Hours),
+          Math.Abs(offset.Minutes)
+        );
       }
     }