GitLab

This CL:
* Introduces ShowKeyboard, HideKeyboard, and IsKeyboardVisible
  to keyboard_controller.mojom.
* Includes HideReason for HideKeyboard (User or System).
* Introduces keyboard::mojom::KeyboardEnableFlag::kTemporarilyEnabled
  for temporarily enabling the keyboard and showing it.
* Renames keyboard::mojom::ReloadKeyboard() -> RebuildKeyboardIfEnabled().
* Introduces keyboard::mojom::ReloadKeyboardIfNeeded() which calls
  KeyboardUI::ReloadKeyboardIfNeeded() which updates the keyboard URL if
  it has changed and otherwise does nothing.
* Replaces direct calls to KeyboardController from most of src/chrome
  Notable exception: ChromeVirtualKeyboardDelegate which will be
  transitioned in a follow up CL.

Bug: 843332
Change-Id: I2faf000c8233ee0253b799a6e4780020ba3bbe1f
Reviewed-on: https://chromium-review.googlesource.com/c/1309215
Commit-Queue: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Reviewed-by: Darren Shen <shend@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Shu Chen <shuchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606311}