Added an option (-i) to have dump_syms output header information only.

src/common/linux/dump_symbols.h

Index: src/common/linux/dump_symbols.h
diff --git a/src/common/linux/dump_symbols.h b/src/common/linux/dump_symbols.h
index 636bb72f73e277272b57975d3b770ec27ce5b6fe..1f204cbadab924f30943216cf3fc211d1b4ede6d 100644
--- a/src/common/linux/dump_symbols.h
+++ b/src/common/linux/dump_symbols.h
@@ -67,6 +67,12 @@ bool WriteSymbolFile(const string &obj_file,
                      const DumpOptions& options,
                      std::ostream &sym_stream);
 
+// Read the selected object file's debugging information, and write out the
+// header only to |stream|. Return true on success; if an error occurs, report
+// it and return false.
+bool WriteSymbolFileHeader(const string& obj_file,
+                           std::ostream &sym_stream);
+
 // As above, but simply return the debugging information in MODULE
 // instead of writing it to a stream. The caller owns the resulting
 // Module object and must delete it when finished.