GitLab

- Make InputMethodMus send changed text client data before
  notifying OnCaretBoundsChanged because InputMethodChromeOS
  processes on the data in its OnCaretBoundsChanged.
- Adjust RemoteTextInputClient::GetTextFromRange to allow empty
  range on empty text. Otherwise, when all text is deleted,
  GetTextFromRange returns false that causes IMEEngine's
  SetSurroundingText not getting called in this scenario and
  breaks suggestions later on.

Bug: 933059, 933019
Change-Id: I93802a78c6c605c5f4dcdb5ea6a806e149745f17
Reviewed-on: https://chromium-review.googlesource.com/c/1478262
Commit-Queue: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#633879}