THRIFT-2297: TJsonProtocol implementation for Delphi does not allow for both possible slash (solidus) encodings, including a test case

Patch: Jens Geyer
diff --git a/lib/delphi/src/Thrift.Protocol.JSON.pas b/lib/delphi/src/Thrift.Protocol.JSON.pas
index 2cc4bbd..cce6c3c 100644
--- a/lib/delphi/src/Thrift.Protocol.JSON.pas
+++ b/lib/delphi/src/Thrift.Protocol.JSON.pas
@@ -264,8 +264,8 @@
                      0,0,0,0, 0,0,0,0, 0,0,0,0,  0,0,0,0,
                      1,1,Byte('"'),1,  1,1,1,1, 1,1,1,1, 1,1,1,1);
 
-  ESCAPE_CHARS     = '"\btnfr';
-  ESCAPE_CHAR_VALS = '"\'#8#9#10#12#13;
+  ESCAPE_CHARS     = '"\/btnfr';
+  ESCAPE_CHAR_VALS = '"\/'#8#9#10#12#13;
 
   DEF_STRING_SIZE = 16;