Rename Properties -> Props

This is for consitency with the PPAPI platform.

BUG=

Review URL: https://codereview.chromium.org/10977007

git-svn-id: https://nativeclient-sdk.googlecode.com/svn/trunk/src@1421 050acbb0-2703-11df-ab0a-9f3f633ae91d
9 files changed