Enable sqlite trunk-stable flags in jni

This change makes trunk-stable flags from the android.database.sqlite
package available to the sqlite jni C++ files.  To use a flag in one
of the SQLite source files (or any C++ file):

````
#include <android_database_sqlite.h>

bool myFlag = android::database::sqlite::my_sqlite_flag();
````

Tested by referencing an existing sqlite flag in
android_database_SQLiteConnection.cpp.  The change to that source file
is not part of this CL.

Bug: 329900153
Change-Id: I3424cdd7a88886e67ed86b7514b8abb919f9fec3