Fix crash in ExtensionService::InitializePermissions().

This crash occurs when an unpacked extension changes IDs by adding a key to its manifest. The extension preferences are stored under the old key. This started causing problems because now we record granted permissions for unpacked extensions.

BUG=112301
TEST=ExtensionServiceTest.UnpackedExtensionCanChangeID

Review URL: https://chromiumcodereview.appspot.com/9320021

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@120123 0039d316-1c4b-4281-b951-d872f2087c98
6 files changed