Fetch snippets from ChromeReader and show them on the NTP

chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsBridge.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsBridge.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsBridge.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsBridge.java
new file mode 100644
index 0000000000000000000000000000000000000000..1a877a6f0216f9690d84fc7d3dc3af7ebe236499
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsBridge.java
@@ -0,0 +1,54 @@
+// 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.ntp.snippets;
+
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.chrome.browser.profiles.Profile;
+
+/**
+ * Provides access to the snippets to display on the NTP using the C++ NTP Snippets Service
+ */
+public class SnippetsBridge {
+    private static final String TAG = "SnippetsBridge";
+
+    private long mNativeSnippetsBridge;
+
+    /**
+     * An observer for notifying when new snippets are loaded
+     */
+    public interface SnippetsObserver {
+        @CalledByNative("SnippetsObserver")
+        public void onSnippetsAvailable(
+                String[] titles, String[] urls, String[] thumbnailUrls, String[] snippets);

[Marc Treib, 2016/02/11 09:23:21]

Optional nit: "snippets" is overloaded to mean both the whole
"title+url+text..." package as well as only the text. Maybe call the text just
"text"?

[May, 2016/02/11 15:25:23]

Done.

+    }
+
+    /**
+     * Creates a SnippetsBridge for getting snippet data for the current user
+     *
+     * @param profile Profile of the user that we will retrieve snippets for.
+     */
+    public SnippetsBridge(Profile profile, final SnippetsObserver observer) {
+        SnippetsObserver wrappedObserver = new SnippetsObserver() {
+            @Override
+            public void onSnippetsAvailable(
+                    String[] titles, String[] urls, String[] thumbnailUrls, String[] snippets) {
+                // Don't notify observer if we've already been destroyed.
+                if (mNativeSnippetsBridge != 0) {
+                    observer.onSnippetsAvailable(titles, urls, thumbnailUrls, snippets);
+                }
+            }
+        };
+        mNativeSnippetsBridge = nativeInit(profile, wrappedObserver);
+    }
+
+    void destroy() {
+        assert mNativeSnippetsBridge != 0;
+        nativeDestroy(mNativeSnippetsBridge);
+        mNativeSnippetsBridge = 0;
+    }
+
+    private native long nativeInit(Profile profile, SnippetsObserver observer);
+    private native void nativeDestroy(long nativeNTPSnippetsBridge);
+}