Revert of https://codereview.chromium.org/100393004/
Reason for revert: Reinstate previous behavior of only showing prompt
for apps with permission warnings. 
The reverted patch was requested by the security team, but there was 
a misunderstanding about whether this was a finch experiment or a 
feature behind command line flags. 

BUG=312460
TBR=benwells@chromium.org
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/109363003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241689 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 241689