Prepare ClearBrowsingDataDialogFragment for browsing data counters.

chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/BrowsingDataCounterBridge.java

Index: chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/BrowsingDataCounterBridge.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/BrowsingDataCounterBridge.java b/chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/BrowsingDataCounterBridge.java
new file mode 100644
index 0000000000000000000000000000000000000000..e84eae3d7ea5701c4f862e5b0402ed1876f1e6ef
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/preferences/privacy/BrowsingDataCounterBridge.java
@@ -0,0 +1,55 @@
+// 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.chrome.browser.preferences.privacy;
+
+import org.chromium.base.annotations.CalledByNative;
+
+/**
+ * Communicates between BrowsingDataCounter (C++ backend) and ClearBrowsingDataFragment (Java UI).
+ */
+public class BrowsingDataCounterBridge {
+    /**
+     * Can receive a callback from a BrowsingDataCounter.
+     */
+    public interface BrowsingDataCounterCallback {
+        /**
+         * The callback to be called when a BrowsingDataCounter is finished.
+         * @param result the result of the counter.

[newt (away), 2016/01/13 20:01:49]

how about: "A string describing how much storage space will be reclaimed by
clearing this data type."

[msramek, 2016/01/14 15:45:43]

Done.

+         */
+        public void onCounterFinished(String result);
+    }
+
+    private long mNativeBrowsingDataCounterBridge;
+    private BrowsingDataCounterCallback mCallback;
+
+    /**
+     * Initializes BrowsingDataCounterBridge.
+     * @param callback a callback to call with the result when the counter finishes.
+     * @param dataType the browsing data type to be counted (from the shared enum
+     *      {@link org.chromium.chrome.browser.BrowsingDataType}).
+     */
+    public BrowsingDataCounterBridge(BrowsingDataCounterCallback callback, int dataType) {
+        mCallback = callback;
+        mNativeBrowsingDataCounterBridge = nativeInit(dataType);
+    }
+
+    /**
+     * Destroys the native counterpart of this class.
+     */
+    public void destroy() {
+        if (mNativeBrowsingDataCounterBridge != 0) {
+            nativeDestroy(mNativeBrowsingDataCounterBridge);
+            mNativeBrowsingDataCounterBridge = 0;
+        }
+    }
+
+    @CalledByNative
+    private void onBrowsingDataCounterFinished(String result) {
+        mCallback.onCounterFinished(result);
+    }
+
+    private native long nativeInit(int dataType);
+    private native void nativeDestroy(long nativeBrowsingDataCounterBridge);
+}