Expose text track settings in Content and implement for Android

content/public/android/java/src/org/chromium/content/browser/accessibility/captioning/KitKatCaptioningBridge.java

Index: content/public/android/java/src/org/chromium/content/browser/accessibility/captioning/KitKatCaptioningBridge.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/accessibility/captioning/KitKatCaptioningBridge.java b/content/public/android/java/src/org/chromium/content/browser/accessibility/captioning/KitKatCaptioningBridge.java
new file mode 100644
index 0000000000000000000000000000000000000000..05b6ba692082963a3e1754ca9bf5ad70e245a4dc
--- /dev/null
+++ b/content/public/android/java/src/org/chromium/content/browser/accessibility/captioning/KitKatCaptioningBridge.java
@@ -0,0 +1,98 @@
+// Copyright 2015 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.accessibility.captioning;
+
+import android.annotation.TargetApi;
+import android.content.Context;
+import android.os.Build;
+import android.view.accessibility.CaptioningManager;
+
+import org.chromium.content.browser.ContentViewCore;
+
+import java.util.Locale;
+
+/**
+ * This is the implementation of SystemCaptioningBridge that uses CaptioningManager
+ * on KitKat+ systems.
+ */
+@TargetApi(Build.VERSION_CODES.KITKAT)
+public class KitKatCaptioningBridge implements SystemCaptioningBridge {
+    private final CaptioningManager.CaptioningChangeListener mCaptioningChangeListener =
+            new KitKatCaptioningChangeListener();
+
+    private final CaptioningChangeDelegate mCaptioningChangeDelegate;
+    private final CaptioningManager mCaptioningManager;
+
+    /**
+     * Bridge listener to inform the mCaptioningChangeDelegate when the mCaptioningManager
+     * broadcasts any changes.
+     */
+    private class KitKatCaptioningChangeListener extends
+            CaptioningManager.CaptioningChangeListener {
+        @Override
+        public void onEnabledChanged(boolean enabled) {
+            mCaptioningChangeDelegate.onEnabledChanged(enabled);
+        }
+
+        @Override
+        public void onFontScaleChanged(float fontScale) {
+            mCaptioningChangeDelegate.onFontScaleChanged(fontScale);
+        }
+
+        @Override
+        public void onLocaleChanged(Locale locale) {
+            mCaptioningChangeDelegate.onLocaleChanged(locale);
+        }
+
+        @Override
+        public void onUserStyleChanged(CaptioningManager.CaptionStyle userStyle) {
+            final CaptioningStyle captioningStyle = getCaptioningStyleFrom(userStyle);
+            mCaptioningChangeDelegate.onUserStyleChanged(captioningStyle);
+        }
+    }
+
+    /**
+     * Construct a new KitKat+ captioning bridge
+     *
+     * @param contentViewCore the ContentViewCore to associate with this bridge.
+     */
+    public KitKatCaptioningBridge(ContentViewCore contenViewCore) {
+        mCaptioningChangeDelegate = new CaptioningChangeDelegate(contenViewCore);
+        mCaptioningManager = (CaptioningManager) contenViewCore.getContext().getSystemService(
+                Context.CAPTIONING_SERVICE);
+        mCaptioningManager.addCaptioningChangeListener(mCaptioningChangeListener);
+        syncToDelegate();
+    }
+
+    /**
+     * Force-sync the current closed caption settings to the delegate
+     */
+    public void syncToDelegate() {
+        mCaptioningChangeDelegate.onEnabledChanged(mCaptioningManager.isEnabled());
+        mCaptioningChangeDelegate.onFontScaleChanged(mCaptioningManager.getFontScale());
+        mCaptioningChangeDelegate.onLocaleChanged(mCaptioningManager.getLocale());
+        mCaptioningChangeDelegate.onUserStyleChanged(
+                getCaptioningStyleFrom(mCaptioningManager.getUserStyle()));
+    }
+
+    /**
+     * De-register this bridge from the system captioning manager. This bridge
+     * should not be used again after this is called.
+     */
+    public void destroy() {
+        mCaptioningManager.removeCaptioningChangeListener(mCaptioningChangeListener);
+    }
+
+    /**
+     * Create a Chromium CaptioningStyle from a platform CaptionStyle
+     *
+     * @param userStyle the platform CaptionStyle
+     * @return a Chromium CaptioningStyle
+     *
+     */
+    private CaptioningStyle getCaptioningStyleFrom(CaptioningManager.CaptionStyle userStyle) {
+        return CaptioningStyle.createFrom(userStyle);
+    }
+}