[Android] Move CommandLine.java to base

The native CommandLine lives in base, and so too should the Java wrapper. Move
CommandLine.java to base, updating all references and factoring out previously
contained switches to BaseSwitches and ContentSwitches.

BUG=320747
TBR=ajwong@chromium.org

Review URL: https://codereview.chromium.org/62333025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236113 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 236113
Add a gin/public directory

When we start using gin from other projects but mojo, we want to be
extra careful what we include. Therefore, we introduce a public/
directories with headers that are ok to be included from gin-embedders.

As a start, we move wrapper_info.h into public/.

BUG=317398
R=abarth@chromium.org

Review URL: https://codereview.chromium.org/69293015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236114 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 236114