Record resource access times

Bug: 246953799

Collect timing information for resource acquisition methods.  The
timing has nanosecond resolution and is collected inside the native
runtime code.  Timing values are accumulated in the runtime and are
periodically fetched and published by the java framework.  This
strategy means that normal resource methods incur a small runtime
overhead.  The longer time involved in publishing the values is
handled by an independent Java thread.

A public dumpTimers() method can be called from a dumpsys command, for
debug, but the dumpsys command is not hooked up in this commit.

No APIs are actually monitored in this commit, and the ResourceTimer
loop is not started.

Test: atest
 * androidfw_lib

Change-Id: I5995d3c6518ca2fa4c8ab9d3eb610167758c695d