Preserves NPObject identity for objects created in a plugin and passed to JavaScript. 

BUG=5751, 22631
TEST=ui_tests w/ the addition of newly added NPObjectIdentityTest.

Patch contributed by Kelly Norton (knorton@google.com), original review: http://codereview.chromium.org/7037027/

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@86893 0039d316-1c4b-4281-b951-d872f2087c98
11 files changed