[Android] Block access to java.lang.Object.getClass in injected Java objects

Throws a java.lang.SecurityException on Browser UI thread when an attempt is
made to execute java.lang.Object.getClass from JavaScript code via an injected
Java object.

BUG=359528

Review URL: https://codereview.chromium.org/213693005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@261801 0039d316-1c4b-4281-b951-d872f2087c98
3 files changed