Change AppFuse mount location to vold namespace

Previously, AppFuse is mounted in system_server's mount namespace. This
CL moves the mount location to vold namespace.

Bug: 110379912
Test: testOpenProxyFileDescriptor passes
Change-Id: Id93c26d5a98842c78f27850c83e15df619cec1ab
diff --git a/VoldNativeService.h b/VoldNativeService.h
index a02fa70..161acb8 100644
--- a/VoldNativeService.h
+++ b/VoldNativeService.h
@@ -75,9 +75,11 @@
     binder::Status runIdleMaint(const android::sp<android::os::IVoldTaskListener>& listener);
     binder::Status abortIdleMaint(const android::sp<android::os::IVoldTaskListener>& listener);
 
-    binder::Status mountAppFuse(int32_t uid, int32_t pid, int32_t mountId,
+    binder::Status mountAppFuse(int32_t uid, int32_t mountId,
                                 android::base::unique_fd* _aidl_return);
-    binder::Status unmountAppFuse(int32_t uid, int32_t pid, int32_t mountId);
+    binder::Status unmountAppFuse(int32_t uid, int32_t mountId);
+    binder::Status openAppFuseFile(int32_t uid, int32_t mountId, int32_t fileId, int32_t flags,
+                                   android::base::unique_fd* _aidl_return);
 
     binder::Status fdeCheckPassword(const std::string& password);
     binder::Status fdeRestart();