Extract method-related information from CompilationUnit.

Extract method-related information, such as class_loader,
class_linker, dex_file, dex_cache, code_item, method_idx,
and access_flags from art::CompilationUnit, so that we
can use them in 2 different code generators.

Change-Id: I20631cc73b6f01e9646a983156f3fcb066d732db
diff --git a/src/compiler_llvm/compiler_llvm.h b/src/compiler_llvm/compiler_llvm.h
index f39f686..13dc063 100644
--- a/src/compiler_llvm/compiler_llvm.h
+++ b/src/compiler_llvm/compiler_llvm.h
@@ -30,6 +30,7 @@
   class CompiledInvokeStub;
   class CompiledMethod;
   class Compiler;
+  class OatCompilationUnit;
 }
 
 
@@ -78,11 +79,7 @@
     return irb_.get();
   }
 
-  CompiledMethod* CompileDexMethod(DexFile::CodeItem const* code_item,
-                                   uint32_t access_flags,
-                                   uint32_t method_idx,
-                                   ClassLoader const* class_loader,
-                                   DexFile const& dex_file);
+  CompiledMethod* CompileDexMethod(OatCompilationUnit* oat_compilation_unit);
 
   CompiledInvokeStub* CreateInvokeStub(bool is_static, char const *shorty);