Refactor compilation out of compsvc

This change makes compsvc always uses dex2oat and no longer accepts
generic executable.

To make the next step of merging ICompService and ICompOsKeyService easier,
the actual compilation setup is extracted from compsvc.rs into a new crate.

Also, remove debuggable flag since it doesn't seem quite useful anymore.

Bug: 194717985
Test: ComposHostTestCases
Change-Id: Ided0c07afb69cd518aed3473d50c5fb695386ca7
diff --git a/compos/src/compos_key_service.rs b/compos/src/compos_key_service.rs
index 779b798..35c04d7 100644
--- a/compos/src/compos_key_service.rs
+++ b/compos/src/compos_key_service.rs
@@ -122,12 +122,7 @@
     fn getCompService(&self, key_blob: &[u8]) -> binder::Result<Strong<dyn ICompService>> {
         let signer =
             Box::new(CompOsSigner { key_blob: key_blob.to_owned(), key_service: self.clone() });
-        let debuggable = true;
-        Ok(compsvc::new_binder(
-            "/apex/com.android.art/bin/dex2oat64".to_owned(),
-            debuggable,
-            Some(signer),
-        ))
+        Ok(compsvc::new_binder(Some(signer)))
     }
 }