Revert "Revert "adb: support /oem partition""

This reverts commit 0c481d0c743382ea955a80bf32428bbd87fff45e.

The original build breakage is fixed by (a) building the verity
code for eng builds as well as userdebug builds and (b) moving
the exported remount service functions into a new header file.

Change-Id: Ice0c4f97d4db38ab7eb333c7a6e56bbd11123f5b
diff --git a/set_verity_enable_state_service.cpp b/set_verity_enable_state_service.cpp
index 85637f2..139b074 100644
--- a/set_verity_enable_state_service.cpp
+++ b/set_verity_enable_state_service.cpp
@@ -26,6 +26,7 @@
 #include "cutils/properties.h"
 #include "ext4_sb.h"
 #include "fs_mgr.h"
+#include "remount_service.h"
 #include "sysdeps.h"
 
 #define FSTAB_PREFIX "/fstab."