Introduce ThreadedInputConnection behind a switch

content/public/android/java/src/org/chromium/content/browser/input/ChromiumBaseInputConnection.java

+// Copyright 2016 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.browser.input;
+
+import android.os.Handler;
+import android.view.KeyEvent;
+import android.view.View;
+import android.view.inputmethod.EditorInfo;
+import android.view.inputmethod.InputConnection;
+
+import org.chromium.base.VisibleForTesting;
+
+/**
+ * An interface to help switch between AdapterInputConnection and ChromiumInputConnection.
+ */
+public interface ChromiumBaseInputConnection extends InputConnection {
+    /**
+     * A factory class to create or reuse ChromiumBaseInputConnection.
+     */
+    public interface Factory {
+        ChromiumBaseInputConnection initializeAndGet(View view, ImeAdapter imeAdapter,
+                int inputType, int inputFlags, EditorInfo outAttrs);
+
+        @VisibleForTesting
+        Handler getHandler();
+    }
+
+    /**
+     * Updates the internal representation of the text being edited and its selection and
+     * composition properties.
+     *
+     * @param text The String contents of the field being edited.
+     * @param selectionStart The character offset of the selection start, or the caret position if
+     *                       there is no selection.
+     * @param selectionEnd The character offset of the selection end, or the caret position if there
+     *                     is no selection.
+     * @param compositionStart The character offset of the composition start, or -1 if there is no
+     *                         composition.
+     * @param compositionEnd The character offset of the composition end, or -1 if there is no
+     *                       selection.
+     * @param isNonImeChange True when the update was caused by non-IME (e.g. Javascript).
+     */
+    void updateStateOnUiThread(String text, int selectionStart, int selectionEnd,
+            int compositionStart, int compositionEnd, boolean singleLine, boolean isNonImeChange);
+
+    /**
+     * Send key event on UI thread.
+     * @param event A key event.
+     */
+    boolean sendKeyEventOnUiThread(KeyEvent event);
+
+    /**
+     * Call this when restartInput() is called.
+     */
+    void onRestartInputOnUiThread();
+
+    /**
+     * @return The {@link Handler} used for this InputConnection.
+     */
+    @VisibleForTesting
+    Handler getHandler();
+
+    /**
+     * Move cursor to the end of the current selection.
+     */
+    void moveCursorToSelectionEndOnUiThread();
+
+    /**
+     * Unblock thread function if needed, e.g. we found that we will
+     * never get state update.
+     */
+    void unblockOnUiThread();
+}