Fix some net/spdy lint picks, from git cl lint.

net/spdy/spdy_write_queue_unittest.cc

 // Copyright (c) 2013 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 "net/spdy/spdy_write_queue.h"
 
 #include <cstddef>
 #include <cstring>
 #include <memory>
 #include <utility>
@@ skipping 32 matching lines @@
 // Makes a SpdyBufferProducer producing a frame with the data in the
 // given int (converted to a string).
 std::unique_ptr<SpdyBufferProducer> IntToProducer(int i) {
   return StringToProducer(base::IntToString(i));
 }
 
 // Producer whose produced buffer will enqueue yet another buffer into the
 // SpdyWriteQueue upon destruction.
 class RequeingBufferProducer : public SpdyBufferProducer {
  public:
-  RequeingBufferProducer(SpdyWriteQueue* queue) {
+  explicit RequeingBufferProducer(SpdyWriteQueue* queue) {
     buffer_.reset(new SpdyBuffer(kOriginal, arraysize(kOriginal)));
     buffer_->AddConsumeCallback(
         base::Bind(RequeingBufferProducer::ConsumeCallback, queue));
   }
 
   std::unique_ptr<SpdyBuffer> ProduceBuffer() override {
     return std::move(buffer_);
   }
 
   size_t EstimateMemoryUsage() const override {
@@ skipping 308 matching lines @@
   base::WeakPtr<SpdyStream> weak_stream;
 
   EXPECT_TRUE(queue.Dequeue(&frame_type, &producer, &weak_stream));
   EXPECT_EQ(SpdyString(kRequeued),
             producer->ProduceBuffer()->GetRemainingData());
 }
 
 }  // namespace
 
 }  // namespace net