Merge r18210....

Merge r18210.

Adds the ability to import the home page of the default browser.  
The import always existed, but was never hooked up to an installerdata 
preference.

BUG=13752
TEST=Run the installer with a line in the distribution block of the 
installerdata that reads: "import_home_page" : true.  The home page of
the previous default browser should be imported.


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=19922