Merge to XFA: Patch from CL 726143002

BUG=https://code.google.com/p/pdfium/issues/detail?id=78
R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/726143002
diff --git a/fpdfsdk/src/javascript/JS_Runtime.cpp b/fpdfsdk/src/javascript/JS_Runtime.cpp
index 260bf20..197d7b4 100644
--- a/fpdfsdk/src/javascript/JS_Runtime.cpp
+++ b/fpdfsdk/src/javascript/JS_Runtime.cpp
@@ -351,7 +351,7 @@
 CFX_WideString ChangeObjName(const CFX_WideString& str)
 {
 	CFX_WideString sRet = str;
-	sRet.Replace((FX_LPCWSTR)L"_", (FX_LPCWSTR)L".");
+	sRet.Replace(L"_", L".");
 	return sRet;
 }