Fix bugs caused by unicode characters in Dropbox-API-Args header

Author: qimingyuan

Dropbox.Api/Babel/IEncodable.cs

@@ -39,10 +39,17 @@ private JsonWriter(JsonTextWriter writer)
         /// <param name="encodable">The object to write.</param>
         /// <param name="encoder">The encoder.</param>
         /// <returns>The encoded object as a JSON string.</returns>
-        public static string Write<T>(T encodable, IEncoder<T> encoder)
+        public static string Write<T>(T encodable, IEncoder<T> encoder, bool escapeNonAscii = false)
         {
             var builder = new StringBuilder();
-            var writer = new JsonWriter(new JsonTextWriter(new StringWriter(builder)));
+            var textWriter = new JsonTextWriter(new StringWriter(builder));
+
+            if (escapeNonAscii)
+            {
+                textWriter.StringEscapeHandling = StringEscapeHandling.EscapeNonAscii;
+            }
+
+            var writer = new JsonWriter(textWriter);
             encoder.Encode(encodable, writer);
 
             var json = builder.ToString();

Dropbox.Api/Babel/JsonWriter.cs

@@ -2,7 +2,7 @@
 <package >
   <metadata>
     <id>$id$</id>
-    <version>2.0.2</version>
+    <version>2.0.3</version>
     <title>Dropbox v2 API Beta</title>
     <authors>Dropbox Inc</authors>
     <owners>Dropbox Inc</owners>

Dropbox.Api/Dropbox.Api.nuspec

@@ -156,9 +156,9 @@ async Task<TResponse> ITransport.SendUploadRequestAsync<TRequest, TResponse, TEr
             IDecoder<TResponse> resposneDecoder,
             IDecoder<TError> errorDecoder)
         {
-            var serializedArg = JsonWriter.Write(request, requestEncoder);
+            var serializedArg = JsonWriter.Write(request, requestEncoder, true);
             var res = await this.RequestJsonStringWithRetry(host, route, RouteStyle.Upload, serializedArg, body);
-
+            
             if (res.IsError)
             {
                 throw ApiException<TError>.Decode(res.ObjectResult, errorDecoder);