Prefer valueOf() to boxed primitive constructors

Constructors for boxed primitives (Byte, Short, Integer, etc) have
long been deprecated. The preferred pattern is to use valueOf(). d8
fails to convert these instances in TypedProperties, most likely due
to the method complexity.

Bug: N/A
Test: Treehugger
Change-Id: Ib58ecc853e2bd1e5d53e9ec256ef0467aa051d9f