inputs: Introduce ExtendSelectionAndReplace/ReplaceSurroundingText API.

ChromeOS has a common operation of "replace some existing text around
the cursor with some new text". This is used in autocorrection, grammar
check, longpress diacritics etc.

This is currently accomplished by doing ExtendSelectionAndDelete (aka
DeleteSurroundingText), followed by a InsertText (aka CommitText).
There are two problems with this:

1) Because it's not atomic, users may see a brief flash.

2) Some websites do not support ExtendSelectionAndDelete correctly.

Introduce a new ExtendSelectionAndReplace/ReplaceSurroundingText API
that can be used by longpress diacritics on ChromeOS. Blink already
supports this operation for Mac, and we can fallback to the two
separate operations for other clients.

Bug: b/279670207,1443726
Change-Id: I797fcd83d4df972ac8828cae31faa9e6c3dc2543
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4485920
Reviewed-by: Robert Kroeger <rjkroege@chromium.org>
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Commit-Queue: Darren Shen <shend@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1142491}

• ash/constants/ash_features.cc[diff]
• ash/constants/ash_features.h[diff]
• chrome/browser/about_flags.cc[diff]
• chrome/browser/ash/input_method/autocorrect_manager_unittest.cc[diff]
• chrome/browser/ash/input_method/emoji_suggester.cc[diff]
• chrome/browser/ash/input_method/emoji_suggester_unittest.cc[diff]
• chrome/browser/ash/input_method/fake_suggestion_handler.cc[diff]
• chrome/browser/ash/input_method/fake_suggestion_handler.h[diff]
• chrome/browser/ash/input_method/grammar_manager_unittest.cc[diff]
• chrome/browser/ash/input_method/input_method_engine.cc[diff]
• chrome/browser/ash/input_method/input_method_engine.h[diff]
• chrome/browser/ash/input_method/input_method_engine_unittest.cc[diff]
• chrome/browser/ash/input_method/longpress_control_v_suggester.cc[diff]
• chrome/browser/ash/input_method/longpress_diacritics_suggester.cc[diff]
• chrome/browser/ash/input_method/suggestion_handler_interface.h[diff]
• chrome/browser/flag-metadata.json[diff]
• chrome/browser/flag_descriptions.cc[diff]
• chrome/browser/flag_descriptions.h[diff]
• components/exo/text_input.cc[diff]
• components/exo/text_input.h[diff]
• content/browser/renderer_host/render_widget_host_view_aura.cc[diff]
• content/browser/renderer_host/render_widget_host_view_aura.h[diff]
• tools/metrics/histograms/enums.xml[diff]
• ui/base/ime/ash/input_method_ash.cc[diff]
• ui/base/ime/ash/input_method_ash.h[diff]
• ui/base/ime/ash/mock_ime_input_context_handler.cc[diff]
• ui/base/ime/ash/mock_ime_input_context_handler.h[diff]
• ui/base/ime/ash/text_input_target.h[diff]
• ui/base/ime/text_input_client.cc[diff]
• ui/base/ime/text_input_client.h[diff]