Add a way to customize boot animation during userspace reboot

In case userspace reboot boot animation can't be found, a default
Android logo is going to be shown.

Test: adb reboot userspace
Bug: 148172262
Change-Id: Ida12ffcfe73b335b63178f3e3f2b0c4063dae2c2
diff --git a/cmds/bootanimation/BootAnimation.h b/cmds/bootanimation/BootAnimation.h
index dc19fb0..574d65e 100644
--- a/cmds/bootanimation/BootAnimation.h
+++ b/cmds/bootanimation/BootAnimation.h
@@ -17,6 +17,8 @@
 #ifndef ANDROID_BOOTANIMATION_H
 #define ANDROID_BOOTANIMATION_H
 
+#include <vector>
+
 #include <stdint.h>
 #include <sys/types.h>
 
@@ -157,6 +159,7 @@
     bool parseAnimationDesc(Animation&);
     bool preloadZip(Animation &animation);
     void findBootAnimationFile();
+    bool findBootAnimationFileInternal(const std::vector<std::string>& files);
     bool preloadAnimation();
 
     void checkExit();