patchoat: add ability to verify relocated .art files

Patchoat can verify that a relocated .art file hasn't been modified
after generation using the --verify flag.

Test: adb shell /system/bin/patchoat --verify \
        --input-image-location=/system/framework/boot.art \
        --output-image-file=/data/dalvik-cache/arm64/system@framework@boot.art \
        --instruction-set=arm64
Bug: 66697305

Change-Id: If6ea02a0527381c520078cd6f3ae2c275a8a8ab1
diff --git a/patchoat/patchoat.h b/patchoat/patchoat.h
index 1033a2e..ba59d57 100644
--- a/patchoat/patchoat.h
+++ b/patchoat/patchoat.h
@@ -53,6 +53,10 @@
                     const std::string& output_image_relocation_directory,
                     InstructionSet isa,
                     TimingLogger* timings);
+  static bool Verify(const std::string& image_location,
+                     const std::string& output_image_filename,
+                     InstructionSet isa,
+                     TimingLogger* timings);
 
   // Generates a patch which can be used to efficiently relocate the original file or to check that
   // a relocated file matches the original. The patch is generated from the difference of the