Make the boot image non-debuggable.

We now support partial fragment deoptimization.

bug:28769520
Change-Id: Ib730f62b6c03882d5e7ae4ce74645eeb7d906ff6
diff --git a/dex2oat/dex2oat.cc b/dex2oat/dex2oat.cc
index cce83f3..db26799 100644
--- a/dex2oat/dex2oat.cc
+++ b/dex2oat/dex2oat.cc
@@ -685,12 +685,6 @@
       Usage("Can't have both --image and (--app-image-fd or --app-image-file)");
     }
 
-    if (IsBootImage()) {
-      // We need the boot image to always be debuggable.
-      // TODO: Remove this once we better deal with full frame deoptimization.
-      compiler_options_->debuggable_ = true;
-    }
-
     if (oat_filenames_.empty() && oat_fd_ == -1) {
       Usage("Output must be supplied with either --oat-file or --oat-fd");
     }