Request Composition Range Updates for Focused GuestViews based on BrowserPlugins

Request Composition Range Updates for Focused GuestViews based on BrowserPlugins

Since the patch https://codereview.chromium.org/2121953002/ landed, composition
range information are only requested for RenderWidgets which have a focused
text input box, that is, their TextInputState.type != ui::TEXT_INPUT_STATE_NONE.

This change however is not implemented for guest views which are based on
BrowserPlugin and therefore, some IME features in Japanese IME have regressed
for <webview>s. While this is not a bug in OOPIF-based guests, it is still an
important bug to fix because:
  1- PDFs will still use BrowserPlugin for a while,
  2- OOPIF-based <webview>'s might not launch in M60.

This patch will add the support by sending the request after BrowserPluginGuest
forwards a TextInputStateChanged call to RenderWidgetHostViewGuest.

BUG=714771
Review-Url: https://codereview.chromium.org/2929543002
Cr-Original-Commit-Position: refs/heads/master@{#479698}
Review-Url: https://codereview.chromium.org/2954963003 .
Cr-Commit-Position: refs/branch-heads/3112@{#466}
Cr-Branched-From: b6460e24cf59f429d69de255538d0fc7a425ccf9-refs/heads/master@{#474897}
Committed: https://chromium.googlesource.com/chromium/src/+/48285bdee11f3f1ed3ec16cbdbce5ddbd8681232

[EhsanK, 2017-06-26 18:23:14]

Description was changed from

==========
Request Composition Range Updates for Focused GuestViews based on BrowserPlugins

Since the patch https://codereview.chromium.org/2121953002/ landed, composition
range information are only requested for RenderWidgets which have a focused
text input box, that is, their TextInputState.type != ui::TEXT_INPUT_STATE_NONE.

This change however is not implemented for guest views which are based on
BrowserPlugin and therefore, some IME features in Japanese IME have regressed
for <webview>s. While this is not a bug in OOPIF-based guests, it is still an
important bug to fix because:
  1- PDFs will still use BrowserPlugin for a while,
  2- OOPIF-based <webview>'s might not launch in M60.

This patch will add the support by sending the request after BrowserPluginGuest
forwards a TextInputStateChanged call to RenderWidgetHostViewGuest.

BUG=714771

Review-Url: https://codereview.chromium.org/2929543002
Cr-Commit-Position: refs/heads/master@{#479698}
(cherry picked from commit 2c3c487604c90c9ce96fefe0a32f660050f9fe55)
==========

to

==========
Request Composition Range Updates for Focused GuestViews based on BrowserPlugins

Since the patch https://codereview.chromium.org/2121953002/ landed, composition
range information are only requested for RenderWidgets which have a focused
text input box, that is, their TextInputState.type != ui::TEXT_INPUT_STATE_NONE.

This change however is not implemented for guest views which are based on
BrowserPlugin and therefore, some IME features in Japanese IME have regressed
for <webview>s. While this is not a bug in OOPIF-based guests, it is still an
important bug to fix because:
  1- PDFs will still use BrowserPlugin for a while,
  2- OOPIF-based <webview>'s might not launch in M60.

This patch will add the support by sending the request after BrowserPluginGuest
forwards a TextInputStateChanged call to RenderWidgetHostViewGuest.

BUG=714771

Review-Url: https://codereview.chromium.org/2929543002
Cr-Original-Commit-Position: refs/heads/master@{#479698}
Review-Url: https://codereview.chromium.org/2954963003 .
Cr-Commit-Position: refs/branch-heads/3112@{#466}
Cr-Branched-From:
b6460e24cf59f429d69de255538d0fc7a425ccf9-refs/heads/master@{#474897}
Committed:
https://chromium.googlesource.com/chromium/src/+/48285bdee11f3f1ed3ec16cbdbce...
==========

[EhsanK, 2017-06-26 18:23:16]

Committed patchset #1 (id:1) manually as
48285bdee11f3f1ed3ec16cbdbce5ddbd8681232.