Refactor jit debugger interface and its ELF creation.

Make it possible to store more then one method per entry,
and ref-count the number of live methods per entry.

Test: m test-art-host-gtest
Change-Id: I45d69185e85e47fbee88a8d1f549ede9875a3c0a
diff --git a/compiler/debug/elf_symtab_writer.h b/compiler/debug/elf_symtab_writer.h
index a853714..9c9e8b3 100644
--- a/compiler/debug/elf_symtab_writer.h
+++ b/compiler/debug/elf_symtab_writer.h
@@ -72,8 +72,8 @@
       continue;  // Add symbol only for the first instance.
     }
     size_t name_offset;
-    if (!info.trampoline_name.empty()) {
-      name_offset = strtab->Write(info.trampoline_name);
+    if (!info.custom_name.empty()) {
+      name_offset = strtab->Write(info.custom_name);
     } else {
       DCHECK(info.dex_file != nullptr);
       std::string name = info.dex_file->PrettyMethod(info.dex_method_index, !mini_debug_info);