Add runtime_native namespace for properties

Create a namespace for runtime native properties, java language
properties will be added in a later CL.

Bug: 111397239
Bug: 120794191
Bug: 123524494

Test: adb shell device_config put runtime_native gctype CC,preverify
Test: verify the property is set correctly
Exempt-From-Owner-Approval: Previously approved

Change-Id: I84ec84f0befdbf778b9cef43991b63fbab3b0943