[SmartText selection] Implement TextClassifier getter and setter

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

Index: content/public/android/java/src/org/chromium/content_public/browser/TextClassifierProvider.java
diff --git a/content/public/android/java/src/org/chromium/content_public/browser/TextClassifierProvider.java b/content/public/android/java/src/org/chromium/content_public/browser/TextClassifierProvider.java
new file mode 100644
index 0000000000000000000000000000000000000000..201c6e6aa66509faabcbab7de023e1f1b2143077
--- /dev/null
+++ b/content/public/android/java/src/org/chromium/content_public/browser/TextClassifierProvider.java
@@ -0,0 +1,17 @@
+// 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;
+
+/**
+ * Stores and returns the TextClassifier object.
+ * The real functionality is implemented by subclass.
+ */
+public class TextClassifierProvider {

[boliu, 2017/04/25 20:30:28]

why is this even needed? Can't WebContents take the classifier directly?

[Tima Vaisburd, 2017/04/25 20:58:02]

I thought it that case WebContents would also have to return the text
classifier, i.e.
implement the logic

  if (!mTextClassifier) {
      return ((TextClassifierManager)mContext.getSystemService(
           Context.TEXT_CLASSIFICATION_SERVICE)).getTextClassifier();

But the TextClassifierManager is only in Android O. So, to avoid reflection I
came up with this...

+    public void setTextClassifier(Object textClassifier) {}
+
+    public Object getTextClassifier() {
+        return null;
+    }
+}