Add -j to dex2oat.

Change-Id: I80f3f2605b8afcdf9adf9382716b041f10efa104
diff --git a/src/common_test.h b/src/common_test.h
index 6adb02d..d55dfbd 100644
--- a/src/common_test.h
+++ b/src/common_test.h
@@ -342,7 +342,7 @@
             runtime_->CreateCalleeSaveMethod(instruction_set, type), type);
       }
     }
-    compiler_.reset(new Compiler(instruction_set, false, NULL));
+    compiler_.reset(new Compiler(instruction_set, false, 2, NULL));
 
     Heap::VerifyHeap();  // Check for heap corruption before the test
   }