[SmartText selection] Implement TextClassifier getter and setter

[SmartText selection] Implement TextClassifier getter and setter

Android API for WebView has the methods
  setTextClassifier
  getTextClassifier

If a user sets the text classifier to a WebView, this classifier
shall be used for smart selection. If none is set, then the system
one shall be used.

Here we create a separate TextClassifierProvider object that can be
created by ContentClassFactory and is owned by WebContents. This
object receives a TextClassifier from the user.

The TextClassifierProvider is passed to the class that request
the classification from the Android API.

BUG=710503

[Tima Vaisburd, 2017-04-25 19:12:57]

timav@chromium.org changed reviewers:
+ boliu@chromium.org

[Tima Vaisburd, 2017-04-25 19:12:59]

PTAL.

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

seems unnecessarily complicated

https://codereview.chromium.org/2835323003/diff/1/android_webview/java/src/or...
File android_webview/java/src/org/chromium/android_webview/AwContents.java
(right):

https://codereview.chromium.org/2835323003/diff/1/android_webview/java/src/or...
android_webview/java/src/org/chromium/android_webview/AwContents.java:63: import
org.chromium.content.browser.ContentClassFactory;
layer violation

https://codereview.chromium.org/2835323003/diff/1/android_webview/java/src/or...
android_webview/java/src/org/chromium/android_webview/AwContents.java:1044: :
ContentClassFactory.get().createTextClassifierProvider(mContext);
simplify the API, if it's null, then content will use the default one

also keep a reference to classifier here so you don't need the getter

https://codereview.chromium.org/2835323003/diff/1/content/public/android/java...
File
content/public/android/java/src/org/chromium/content/browser/ContextSelectionClient.java
(right):

https://codereview.chromium.org/2835323003/diff/1/content/public/android/java...
content/public/android/java/src/org/chromium/content/browser/ContextSelectionClient.java:55:
TextClassifierProvider tc_provider = webContents.getTextClassifierProvider();
camelCase

https://codereview.chromium.org/2835323003/diff/1/content/public/android/java...
content/public/android/java/src/org/chromium/content/browser/ContextSelectionClient.java:57:
Log.e(TAG, "Cannot create object: no TextClassifierProvider");
assert, don't log

https://codereview.chromium.org/2835323003/diff/1/content/public/android/java...
File
content/public/android/java/src/org/chromium/content_public/browser/TextClassifierProvider.java
(right):

https://codereview.chromium.org/2835323003/diff/1/content/public/android/java...
content/public/android/java/src/org/chromium/content_public/browser/TextClassifierProvider.java:11:
public class TextClassifierProvider {
why is this even needed? Can't WebContents take the classifier directly?

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

https://codereview.chromium.org/2835323003/diff/1/content/public/android/java...
File
content/public/android/java/src/org/chromium/content_public/browser/TextClassifierProvider.java
(right):

https://codereview.chromium.org/2835323003/diff/1/content/public/android/java...
content/public/android/java/src/org/chromium/content_public/browser/TextClassifierProvider.java:11:
public class TextClassifierProvider {
On 2017/04/25 20:30:28, boliu wrote:
> why is this even needed? Can't WebContents take the classifier directly?

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...

[Tima Vaisburd, 2017-05-13 02:42:50]

Closing this CL since a better approach is done in
https://codereview.chromium.org/2882583004