The jschar typedef is removed in SpiderMonkey 38.

Since it already is char16_t in 31 replace it by that.
https://bugzilla.mozilla.org/show_bug.cgi?id=1063962

This was SVN commit r17506.

source/scriptinterface/ThreadDebugger.cpp

@@ -785,7 +785,7 @@ namespace CyclicRefWorkaround
 	
 	struct Stringifier
 	{
-		static bool callback(const jschar* buf, uint32 len, void* data)
+		static bool callback(const char16_t* buf, uint32 len, void* data)
 		{
 			utf16string str(buf, buf+len);
 			std::wstring strw(str.begin(), str.end());