Add Mojo IPC for seeding new Renderer with Browser's cached blob state.

blimp/net/blob_channel/mock_blob_channel_sender.h

 // 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.
 
 #ifndef BLIMP_NET_BLOB_CHANNEL_MOCK_BLOB_CHANNEL_SENDER_H_
 #define BLIMP_NET_BLOB_CHANNEL_MOCK_BLOB_CHANNEL_SENDER_H_
 
 #include <string>
 #include <vector>
 
 #include "blimp/net/blob_channel/blob_channel_sender.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
 namespace blimp {
 
 class BLIMP_NET_EXPORT MockBlobChannelSender : public BlobChannelSender {
  public:
   MockBlobChannelSender();
   ~MockBlobChannelSender() override;
 
   MOCK_METHOD2(PutBlob, void(const BlobId& id, BlobDataPtr data));
   MOCK_METHOD1(DeliverBlob, void(const BlobId& id));
+  MOCK_CONST_METHOD0(GetCachedBlobIds, std::vector<CacheStateEntry>());
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MockBlobChannelSender);
 };
 
 }  // namespace blimp
 
 #endif  // BLIMP_NET_BLOB_CHANNEL_MOCK_BLOB_CHANNEL_SENDER_H_