Change the method which generates DWARF mini-debug-info.

This splits some code from CL198651. It moves the WriteSection
call out one level and does not otherwise change behaviour.

Change-Id: I7dc1c7c08b577b50bf6fa366a9b0ca757048b81e
diff --git a/compiler/elf_writer_debug.h b/compiler/elf_writer_debug.h
index 8e8472f..e289197 100644
--- a/compiler/elf_writer_debug.h
+++ b/compiler/elf_writer_debug.h
@@ -36,9 +36,10 @@
                     CFIFormat cfi_format,
                     bool write_oat_patches);
 
-template <typename ElfTypes>
-void WriteMiniDebugInfo(ElfBuilder<ElfTypes>* builder,
-                        const ArrayRef<const MethodDebugInfo>& method_infos);
+std::vector<uint8_t> MakeMiniDebugInfo(InstructionSet isa,
+                                       size_t rodata_section_size,
+                                       size_t text_section_size,
+                                       const ArrayRef<const MethodDebugInfo>& method_infos);
 
 ArrayRef<const uint8_t> WriteDebugElfFileForMethod(const dwarf::MethodDebugInfo& method_info);