Add a way to send the resource percentage signal to the RC.

components/offline_pages/core/background/resource_tracker_observer_stub.cc

Index: components/offline_pages/core/background/resource_tracker_observer_stub.cc
diff --git a/components/offline_pages/core/background/resource_tracker_observer_stub.cc b/components/offline_pages/core/background/resource_tracker_observer_stub.cc
new file mode 100644
index 0000000000000000000000000000000000000000..c2408719e6c74c3bfe274d37d7ea483cbbc5070e
--- /dev/null
+++ b/components/offline_pages/core/background/resource_tracker_observer_stub.cc
@@ -0,0 +1,41 @@
+// Copyright 2017 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.
+
+#include "components/offline_pages/core/background/resource_tracker_observer_stub.h"
+
+namespace offline_pages {
+
+ResourceTrackerObserverStub::ResourceTrackerObserverStub()
+    : images_started_(0), images_completed_(0) {}
+
+ResourceTrackerObserverStub::~ResourceTrackerObserverStub() {}
+
+// When we are notified of a resource load starting or ending, pass the
+// information along to the offliner.
+// TODO(petewil): Today this just supports images, expand to support all types.
+void ResourceTrackerObserverStub::ObserveResourceTracking(
+    const ResourceDataType type,
+    int64_t started_count,
+    int64_t completed_count) {
+  if (type == ResourceDataType::IMAGE) {
+    images_started_ = started_count;
+    images_completed_ = completed_count;
+  }
+}
+
+// Returns the most recently seen counts for a specific resource type.
+// TODO(petewil): Today this just supports images, later support all types.
+void ResourceTrackerObserverStub::GetResourcePercentageCounts(
+    const ResourceDataType type,
+    int64_t* started,
+    int64_t* completed) {
+  if (type == ResourceDataType::IMAGE) {
+    if (started)
+      *started = images_started_;
+    if (completed)
+      *completed = images_completed_;
+  }
+}
+
+}  // namespace offline_pages