Split elf_writer_debug.cc to several files.

Refactoring only. The file has grown significantly over time,
and it is time to split it so it can be better managed.

Change-Id: Idce0231718add722292f4701df353d5baf31de5f
diff --git a/compiler/oat_writer.h b/compiler/oat_writer.h
index 14c6d50..5a55fc6 100644
--- a/compiler/oat_writer.h
+++ b/compiler/oat_writer.h
@@ -43,9 +43,9 @@
 class TypeLookupTable;
 class ZipEntry;
 
-namespace dwarf {
+namespace debug {
 struct MethodDebugInfo;
-}  // namespace dwarf
+}  // namespace debug
 
 // OatHeader         variable length with count of D OatDexFiles
 //
@@ -193,8 +193,8 @@
 
   ~OatWriter();
 
-  ArrayRef<const dwarf::MethodDebugInfo> GetMethodDebugInfo() const {
-    return ArrayRef<const dwarf::MethodDebugInfo>(method_info_);
+  ArrayRef<const debug::MethodDebugInfo> GetMethodDebugInfo() const {
+    return ArrayRef<const debug::MethodDebugInfo>(method_info_);
   }
 
   const CompilerDriver* GetCompilerDriver() {
@@ -289,7 +289,7 @@
   // We need this because we keep plain pointers to the strings' c_str().
   std::list<std::string> zipped_dex_file_locations_;
 
-  dchecked_vector<dwarf::MethodDebugInfo> method_info_;
+  dchecked_vector<debug::MethodDebugInfo> method_info_;
 
   const CompilerDriver* compiler_driver_;
   ImageWriter* image_writer_;