Expose registered histograms from FeedbackCollector

base/android/java/src/org/chromium/base/metrics/StatisticsRecorderAndroid.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.base.metrics;
+
+import org.chromium.base.annotations.JNINamespace;
+
+/**
+ * Java API which exposes the registered histograms on the native side as
+ * JSON test.
+ */
+@JNINamespace("base::android")
+public final class StatisticsRecorderAndroid {
+    private StatisticsRecorderAndroid() {}
+
+    /**
+      * @return All the registered histograms as JSON text.
+      */
+    public static String toJson() {
+        return nativeToJson();
+    }
+
+    private static native String nativeToJson();
+}