Make ArcImeService a focused TextInputClient while an inline reply is focused.

ArcImeService implements a TextInputClient interface to support IME
operations on a text field on ARC++.
Before this CL, it's used only when a text field on ARC++ apps is
focused.
ArcImeService should be active also when an inline reply on ARC++
notifications are focused.

Bug: 1168334
Test: manual - confirm composing works on inline reply
Change-Id: Ib374be7c8325aa6edb62712a0317a25ea893b8d9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2639334Reviewed-by: Tetsui Ohkubo <tetsui@chromium.org>
Commit-Queue: Yuichiro Hanada <yhanada@chromium.org>
Cr-Commit-Position: refs/heads/master@{#845072}

components/arc/ime/arc_ime_service.cc

@@ -60,6 +60,12 @@ class ArcWindowDelegateImpl : public ArcImeService::ArcWindowDelegate {
       if (ash::IsArcWindow(window))
         return true;
 
+      // TODO(crbug.com/1168334): Find a correct way to detect the ARC++
+      // notifications. It should be okay for now because only the ARC++ windows
+      // have kSkipImeProcessing.
+      if (window->GetProperty(aura::client::kSkipImeProcessing))
+        return true;
+
       // IsArcAppWindow returns false for a window of ARC++ Kiosk app, so we
       // have to check application id of the active window to cover that case.
       // TODO(yhanada): Make IsArcAppWindow support a window of ARC++ Kiosk.