Add unit tests for the Background Scheduler.

chrome/android/java/src/org/chromium/chrome/browser/offlinepages/interfaces/SchedulerBridgeInterface.java

Index: chrome/android/java/src/org/chromium/chrome/browser/offlinepages/interfaces/SchedulerBridgeInterface.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/interfaces/SchedulerBridgeInterface.java b/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/interfaces/SchedulerBridgeInterface.java
new file mode 100644
index 0000000000000000000000000000000000000000..9dc86461532c18dbc59c3f57374526830b8b3c3c
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/interfaces/SchedulerBridgeInterface.java
@@ -0,0 +1,25 @@
+// 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.offlinepages.interfaces;
+
+/**
+ * Interface to allow mocking out the SchedulerBridge, which must call static methods.
+ */
+public abstract interface SchedulerBridgeInterface {

[chili, 2016/06/02 00:37:25]

why are we declaring an interface abstract?  Aren't interfaces by definition
abstract?

Also, can we drop the Interface in SchedulerBridgeInterface?  We declare it as
an interface already, so that seems redundant (we can rename SchedulerBridge to
SchedulerBridgeImpl?).  Feel free to ignore if this is for consistency

[Pete Williamson, 2016/06/02 20:51:33]

Done.

+    // Starts processing of one or more queued background requests.  Returns whether processing was
+    // started and that caller should expect a callback (once processing has completed or
+    // terminated).  If processing was already active or not able to process for some other reason,
+    // returns false and this calling instance will not receive a callback.
+    public abstract boolean startProcessing(
+            SchedulerBridgeInterface.ProcessingDoneCallback callback);
+
+    /**
+     * Callback used to determine when request processing is done.
+     */
+    public interface ProcessingDoneCallback {
+        void onProcessingDone(boolean result);
+    }
+
+}