Enrich the dictionary with many words generated from stems
extracted from the dictionary and rules written by hand.
This adds 45,619 words to the dictionary. Hopefully, almost none
of them is incorrect, though a lot are not very common.

Bug: 8010862
Change-Id: I51c7ebd16ff859ec1e765b0604dd1cfca159ab08

Change-Id: I4cbae476d16723778b46ff765dd97832f279785f

Bug: 14602663
Change-Id: Ie2060931df911b44230d5a5ba268f687cbdd0dc8

Bug: 12491371
Change-Id: I1f7feef707b95e8862db71cbc4f6f5585a2441dd

Bug: 13336905
Change-Id: Iefd117fa7b30b8ba240590b13b03d7044fd37ede

Bug: 12491371
Change-Id: Ib7ca91ae73aa40e45ea5f6d4e53348a261a4b823

Bug: 12491371
Change-Id: I3ce1e6557e41a94146b882751f75ae4b5f6bc73d

* commit '61a8a66c':
  Workaround to draw spacebar icon of emoji palettes

* commit 'ee4cc67e':
  Update shift key icon for LXX_Dark

Bug: 15321822
Change-Id: Iab7cef83ffdf91c877c3ed2e59d412496b516e1c

Bug: 15310025
Change-Id: I20bde50a2e751a5cd9871debd5ed1df0334c78e2

This fixes PunctuationTests#
testAutoCorrectionWithSingleQuotesAround.

Bug: 14119293
Bug: 15334309

Change-Id: I604c21a21e89a5fc431fd56ab7b6ad03f4736b01

* commit 'ba8836a9':
  Update action key backgrounds for LXX_Dark

* commit 'db2d6a20':
  Update enter and send icons for LXX_Dark

* commit '3d5a72eb':
  Update spacebar icon of LXX_Dark

Bug: 15295839
Change-Id: I77206c88c38a31193db97ce42c9d00fc25c7ff58

Bug: 15298065
Bug: 15327280
Change-Id: I4dfade1afe3578e29daba777567f81d4ec782956

This CL does't fix Bug: 15321822 though.

Bug: 15298065
Bug: 15321822
Change-Id: Ie6ab1e230c1657317dc06193da598f04f682f521

At 100k text, it's reasonably fast (less than 1s on latest hardware).

Bug: 12913404
Change-Id: I426b918b2610af24364934a1c37a7314f1142ad0

* commit '761a6812':
  Don't reuse main keyboard's spacebar icon for Emoji palette

Bug: 15321822
Change-Id: I6a5a865364fb98e0ebb6206d80d5629bbcb817b8

DEBUG in LatinIME has been changed by Ie52007dc to mean both
DebugSettings.PREF_DEBUG_MODE and Settings.PREF_KEY_IS_INTERNAL
instead of just DEBUG_MODE as used to be the case. Tests depend
on the debug mode to test many things and they make sure they run
in debug mode or they fail. This has tests understand the change in
policy.

Change-Id: Ie9f29e6a1d85e19704c8940d3fcf97c13c3dbaa6

* commit 'cdc7273b':
  Update action key background

Change-Id: Ie1cdc5642d8b6f63dbf71603b993f36b5c5f923c

Bug: 15295839
Change-Id: Ia4af33b00bf361d088981df907468b4a61c1a076

This CL must be checked in together with Ie52007dc5c.

Bug: 15318007
Change-Id: Ie665f296e43b5485ae8ba7e949aa262794ee0dcc

This reverts commit d941ea18 and builds on it to fix the behavior
of the broken cases.
It also fixes a small, related bug that probably has existed for
a very long time: predictions not displayed when cancelling
double-space-to-period.

Bug: 15148015
Change-Id: I1f9358f8b6f5804f831643611576be347e83999d

Bug: 15320560
Change-Id: Icb88a96ebd685da1d2cba7b07889a2751c603a2e

Bug: 11778342
Change-Id: Ice88f439ae11714e5ec9dd3b7616d0c2d59ea812

This CL must be checked in together with I5cc76807e3.

Bug: 15318007
Change-Id: I61423c3377ddc299fb332e742d6626c2e47145bb