Fix Chromium clang plugin warnings

webrtc/common_audio/lapped_transform.h

 /*
  *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 35 matching lines @@
   // |block_length| defines the length of a block, in samples.
   // |shift_amount| is in samples. |callback| is the caller-owned audio
   // processing function called for each block of the input chunk.
   LappedTransform(size_t num_in_channels,
                   size_t num_out_channels,
                   size_t chunk_length,
                   const float* window,
                   size_t block_length,
                   size_t shift_amount,
                   Callback* callback);
-  ~LappedTransform() {}
+  ~LappedTransform();
 
   // Main audio processing helper method. Internally slices |in_chunk| into
   // blocks, transforms them to frequency domain, calls the callback for each
   // block and returns a de-blocked time domain chunk of audio through
   // |out_chunk|. Both buffers are caller-owned.
   void ProcessChunk(const float* const* in_chunk, float* const* out_chunk);
 
   // Get the chunk length.
   //
   // The chunk length is the number of samples per channel that must be passed
@@ skipping 19 matching lines @@
   // constructor.
   size_t num_out_channels() const { return num_out_channels_; }
 
  private:
   // Internal middleware callback, given to the blocker. Transforms each block
   // and hands it over to the processing method given at construction time.
   class BlockThunk : public BlockerCallback {
    public:
     explicit BlockThunk(LappedTransform* parent) : parent_(parent) {}
 
-    virtual void ProcessBlock(const float* const* input,
+ void ProcessBlock(const float* const* input,
                               size_t num_frames,
                               size_t num_input_channels,
                               size_t num_output_channels,
-                              float* const* output);
+                              float* const* output) override;
 
    private:
     LappedTransform* const parent_;
   } blocker_callback_;
 
   const size_t num_in_channels_;
   const size_t num_out_channels_;
 
   const size_t block_length_;
   const size_t chunk_length_;
 
   Callback* const block_processor_;
   Blocker blocker_;
 
   std::unique_ptr<RealFourier> fft_;
   const size_t cplx_length_;
   AlignedArray<float> real_buf_;
   AlignedArray<std::complex<float> > cplx_pre_;
   AlignedArray<std::complex<float> > cplx_post_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_COMMON_AUDIO_LAPPED_TRANSFORM_H_