Make base::RefCountedBase methods inline

Re-applying of the reverted https://codereview.chromium.org/88993002/ as it gives significant performance improvement.

Please see http://code.google.com/p/chromium/issues/detail?id=328329 for the details.

BUG=328329

Review URL: https://codereview.chromium.org/119143003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241937 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 241937
Add base:: namespace to string16s in chromeos/.

R=satorux@chromium.org
BUG=329295

Review URL: https://codereview.chromium.org/105143013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241938 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 241938