Revert of Migrate IME state update flow

content/public/android/java/src/org/chromium/content_public/browser/ImeEventObserver.java

Index: content/public/android/java/src/org/chromium/content_public/browser/ImeEventObserver.java
diff --git a/content/public/android/java/src/org/chromium/content_public/browser/ImeEventObserver.java b/content/public/android/java/src/org/chromium/content_public/browser/ImeEventObserver.java
deleted file mode 100644
index 5ba308fa2ec14d33007a749f16de41c8384c41f1..0000000000000000000000000000000000000000
--- a/content/public/android/java/src/org/chromium/content_public/browser/ImeEventObserver.java
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2017 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-package org.chromium.content_public.browser;
-
-/**
- * Interface for the classes that need to be notified of IME changes.
- */
-public interface ImeEventObserver {
-    /**
-     * Called to notify the delegate about synthetic/real key events before sending to renderer.
-     */
-    void onImeEvent();
-
-    /**
-     * Called when the focused node attribute is updated.
-     * @param editable {@code true} if the node becomes editable; else {@code false}.
-     * @param password indicates the node is of type password if {@code true}.
-     */
-    void onNodeAttributeUpdated(boolean editable, boolean password);
-}