[PATCH] Add DWARFFormValue::getAsSignedConstant().

[Alexey Samsonov]

================
Comment at: unittests/DebugInfo/DWARFFormValueTest.cpp:10
@@ -9,2 +9,3 @@
 
+#include "../lib/DebugInfo/DWARFContext.h"
 #include "llvm/DebugInfo/DWARFFormValue.h"
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Unittests may only include headers from include/llvm (i.e., public headers). If we want to add unittests that instantiate DWARFContext, we should make corresponding header public.

http://reviews.llvm.org/D5630