[esan|cfrag] Handle binaries built with -esan-aux-field-info=false

Summary:
Handles binaries built with -esan-aux-field-info=false and print less
information.

Updates test struct-simple.cpp.

Reviewers: aizatsky

Subscribers: llvm-commits, bruening, eugenis, kcc, zhaoqin, kubabrecka, vitalybuka

Differential Revision: http://reviews.llvm.org/D22020

llvm-svn: 274727