Attempt to use dictionary facilitor without invoking
preference manager. Instead use account from settings only when
things are being reset/changed. Discussion forked from ag/591663

Overall, the idea here is to maintain an account information
inside dictionary groups. Reset the dictionary groups if
account changes (the way we do for locale). Since only user
history dictionary is currently affected, the check to reset user
history dictionary also includes the check to verify the account.
For other things remain the same.

SettingsValues holds the current account (and is updated if prefs change
due to change in account settings). The updated settings are then
propagated to dictionary facilitator via LatinIME#loadSettings.

Bug:18104749,18469539
Change-Id: I553e776e7ea125d0fb7a1fe70a4c7eb0b2277fb8

5Bug: 14425059
Change-Id: I73cf6904e569d60996a3b079f16ea6df0cb90f02

This is the central change of multilingual input.

Bug: 11230254
Change-Id: Id8b68fb101e837e8cf182ab4bc1e55e4da5cc49d

This change rewrites resetDictionariesWithDictNamePrefix so
that it would work if there were several locales, which is going to
happen shortly. This change on its own is quite large and difficult
already, so I didn't want to merge it into the change that actually
makes several locales happen; another such change is following.

Change-Id: Ibb80b05b73c0f0f0bea64b7e308cc4d38ca448f9

Bug: 16547557
Change-Id: I03eda34edc902fc4732d16d234216344d8d84d88

Bug: 16547557
Change-Id: If3d88a548e5a2255ff81c819b056f77bfbe237ae