[Android] Expose additional ViewConfiguration-related constants

Add additional constants to the C++ wrapper of ViewConfiguration, as required
by the future port of GestureDetector and ScaleGestureDetector to native code.
Also cache constants upon first access, synchronizing access to those values
that may change if the DPI scale changes.

BUG=332418,344370
NOTRY=true

Review URL: https://codereview.chromium.org/171013004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252401 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252401