Add option to specify compiler executable.

Change-Id: I973da5e74be5a62461caacbc708288fb95e1b99b
diff --git a/runtime/parsed_options.h b/runtime/parsed_options.h
index e0b0fb5..25fc12a 100644
--- a/runtime/parsed_options.h
+++ b/runtime/parsed_options.h
@@ -74,6 +74,7 @@
   void (*hook_exit_)(jint status);
   void (*hook_abort_)();
   std::vector<std::string> properties_;
+  std::string compiler_executable_;
   std::vector<std::string> compiler_options_;
   std::vector<std::string> image_compiler_options_;
   bool profile_;