[PATCH] Add test for r211904 - llvm-objdump: don't assert if ELF file has no sections

[Ed Maste]

================
Comment at: test/Object/objdump-no-sectionheaders.test:4
@@ +3,3 @@
+
+; CHECK: Sections:
+; CHECK: Idx Name          Size      Address          Type
----------------
Some tools e.g. readelf explicitly report that the section table is empty / does not exist - e.g. `There are no sections in this file.`

GNU objdump matches this behaviour - i.e., outputs the header, but an empty table.
```
Sections:
Idx Name          Size      VMA               LMA               File off  Algn
```

This output seems reasonable to me - I just don't know how to match the EOF with lit in order to verify that no sections were output.

http://reviews.llvm.org/D4349