Modify search engine dialog to only appear if the user does not have an existing preferences file.
Modify search engine dialog to only appear if the user does not have an existing preferences file.

LGTM from Glen in http://codereview.chromium.org/3232001/show for patch to 472 branch.

BUG=53485
TEST=search engine dialog works and appears only when user does not have a previously existing user data directory.  If user has already run Chrome and set up a user data directory, dialog should not appear, and search engines should be silently imported (in organic builds).

Review URL: http://codereview.chromium.org/3242004

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@57685 0039d316-1c4b-4281-b951-d872f2087c98

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