Update audio_processing module

Corresponds to upstream commit 524e9b043e7e86fd72353b987c9d5f6a1ebf83e1

Update notes:

 * Pull in third party license file

 * Replace .gypi files with BUILD.gn to keep track of what changes
   upstream

 * Bunch of new filse pulled in as dependencies

 * Won't build yet due to changes needed on top of these

webrtc/modules/audio_processing/beamformer/complex_matrix.h

@@ -0,0 +1,97 @@
+/*
+ *  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.
+ */
+
+#ifndef WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_COMPLEX_MATRIX_H_
+#define WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_COMPLEX_MATRIX_H_
+
+#include <complex>
+
+#include "webrtc/base/checks.h"
+#include "webrtc/base/scoped_ptr.h"
+#include "webrtc/modules/audio_processing/beamformer/matrix.h"
+
+namespace webrtc {
+
+using std::complex;
+
+// An extension of Matrix for operations that only work on a complex type.
+template <typename T>
+class ComplexMatrix : public Matrix<complex<T> > {
+ public:
+  ComplexMatrix() : Matrix<complex<T> >() {}
+
+  ComplexMatrix(int num_rows, int num_columns)
+      : Matrix<complex<T> >(num_rows, num_columns) {}
+
+  ComplexMatrix(const complex<T>* data, int num_rows, int num_columns)
+      : Matrix<complex<T> >(data, num_rows, num_columns) {}
+
+  // Complex Matrix operations.
+  ComplexMatrix& PointwiseConjugate() {
+    complex<T>* const data = this->data();
+    size_t size = this->num_rows() * this->num_columns();
+    for (size_t i = 0; i < size; ++i) {
+      data[i] = conj(data[i]);
+    }
+
+    return *this;
+  }
+
+  ComplexMatrix& PointwiseConjugate(const ComplexMatrix& operand) {
+    this->CopyFrom(operand);
+    return PointwiseConjugate();
+  }
+
+  ComplexMatrix& ConjugateTranspose() {
+    this->CopyDataToScratch();
+    int num_rows = this->num_rows();
+    this->SetNumRows(this->num_columns());
+    this->SetNumColumns(num_rows);
+    this->Resize();
+    return ConjugateTranspose(this->scratch_elements());
+  }
+
+  ComplexMatrix& ConjugateTranspose(const ComplexMatrix& operand) {
+    RTC_CHECK_EQ(operand.num_rows(), this->num_columns());
+    RTC_CHECK_EQ(operand.num_columns(), this->num_rows());
+    return ConjugateTranspose(operand.elements());
+  }
+
+  ComplexMatrix& ZeroImag() {
+    complex<T>* const data = this->data();
+    size_t size = this->num_rows() * this->num_columns();
+    for (size_t i = 0; i < size; ++i) {
+      data[i] = complex<T>(data[i].real(), 0);
+    }
+
+    return *this;
+  }
+
+  ComplexMatrix& ZeroImag(const ComplexMatrix& operand) {
+    this->CopyFrom(operand);
+    return ZeroImag();
+  }
+
+ private:
+  ComplexMatrix& ConjugateTranspose(const complex<T>* const* src) {
+    complex<T>* const* elements = this->elements();
+    for (int i = 0; i < this->num_rows(); ++i) {
+      for (int j = 0; j < this->num_columns(); ++j) {
+        elements[i][j] = conj(src[j][i]);
+      }
+    }
+
+    return *this;
+  }
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_COMPLEX_MATRIX_H_