Update unit test for the function of enumNameOrThrow
Update unit test for the function of enumNameOrThrow

Summary: Replace EXPECT_EQ with EXPECT_THROW in the function of enumNameOrThrow since throw an exception is enough and the error message is not essential.

Reviewed By: Mizuchi

Differential Revision: D29539748

fbshipit-source-id: 0ea86fbeb8a88c099955a18f2d2877271ef6248c

facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift