Make image test multi image

Required for testing multi image layout in future CLs.

Bug: 28640955

Test: clean-oat-host, test-art-host, device booting

(cherry picked from commit 25adcfb7dc81131add3a0a681ae18bced6f7a0e0)

Change-Id: I14809f56e711b4a87e01056c327eddbbd087f4ee
diff --git a/runtime/common_runtime_test.h b/runtime/common_runtime_test.h
index b2090b7..2376e6a 100644
--- a/runtime/common_runtime_test.h
+++ b/runtime/common_runtime_test.h
@@ -40,8 +40,14 @@
  public:
   ScratchFile();
 
+  explicit ScratchFile(const std::string& filename);
+
   ScratchFile(const ScratchFile& other, const char* suffix);
 
+  explicit ScratchFile(ScratchFile&& other);
+
+  ScratchFile& operator=(ScratchFile&& other);
+
   explicit ScratchFile(File* file);
 
   ~ScratchFile();