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/base/stringutils.cc

@@ -0,0 +1,133 @@
+/*
+ *  Copyright 2004 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.
+ */
+
+#include "webrtc/base/checks.h"
+#include "webrtc/base/stringutils.h"
+
+namespace rtc {
+
+bool memory_check(const void* memory, int c, size_t count) {
+  const char* char_memory = static_cast<const char*>(memory);
+  char char_c = static_cast<char>(c);
+  for (size_t i = 0; i < count; ++i) {
+    if (char_memory[i] != char_c) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool string_match(const char* target, const char* pattern) {
+  while (*pattern) {
+    if (*pattern == '*') {
+      if (!*++pattern) {
+        return true;
+      }
+      while (*target) {
+        if ((toupper(*pattern) == toupper(*target))
+            && string_match(target + 1, pattern + 1)) {
+          return true;
+        }
+        ++target;
+      }
+      return false;
+    } else {
+      if (toupper(*pattern) != toupper(*target)) {
+        return false;
+      }
+      ++target;
+      ++pattern;
+    }
+  }
+  return !*target;
+}
+
+#if defined(WEBRTC_WIN)
+int ascii_string_compare(const wchar_t* s1, const char* s2, size_t n,
+                         CharacterTransformation transformation) {
+  wchar_t c1, c2;
+  while (true) {
+    if (n-- == 0) return 0;
+    c1 = transformation(*s1);
+    // Double check that characters are not UTF-8
+    RTC_DCHECK_LT(static_cast<unsigned char>(*s2), 128);
+    // Note: *s2 gets implicitly promoted to wchar_t
+    c2 = transformation(*s2);
+    if (c1 != c2) return (c1 < c2) ? -1 : 1;
+    if (!c1) return 0;
+    ++s1;
+    ++s2;
+  }
+}
+
+size_t asccpyn(wchar_t* buffer, size_t buflen,
+               const char* source, size_t srclen) {
+  if (buflen <= 0)
+    return 0;
+
+  if (srclen == SIZE_UNKNOWN) {
+    srclen = strlenn(source, buflen - 1);
+  } else if (srclen >= buflen) {
+    srclen = buflen - 1;
+  }
+#if _DEBUG
+  // Double check that characters are not UTF-8
+  for (size_t pos = 0; pos < srclen; ++pos)
+    RTC_DCHECK_LT(static_cast<unsigned char>(source[pos]), 128);
+#endif  // _DEBUG
+  std::copy(source, source + srclen, buffer);
+  buffer[srclen] = 0;
+  return srclen;
+}
+
+#endif  // WEBRTC_WIN
+
+void replace_substrs(const char *search,
+                     size_t search_len,
+                     const char *replace,
+                     size_t replace_len,
+                     std::string *s) {
+  size_t pos = 0;
+  while ((pos = s->find(search, pos, search_len)) != std::string::npos) {
+    s->replace(pos, search_len, replace, replace_len);
+    pos += replace_len;
+  }
+}
+
+bool starts_with(const char *s1, const char *s2) {
+  return strncmp(s1, s2, strlen(s2)) == 0;
+}
+
+bool ends_with(const char *s1, const char *s2) {
+  size_t s1_length = strlen(s1);
+  size_t s2_length = strlen(s2);
+
+  if (s2_length > s1_length) {
+    return false;
+  }
+
+  const char* start = s1 + (s1_length - s2_length);
+  return strncmp(start, s2, s2_length) == 0;
+}
+
+static const char kWhitespace[] = " \n\r\t";
+
+std::string string_trim(const std::string& s) {
+  std::string::size_type first = s.find_first_not_of(kWhitespace);
+  std::string::size_type last  = s.find_last_not_of(kWhitespace);
+
+  if (first == std::string::npos || last == std::string::npos) {
+    return std::string("");
+  }
+
+  return s.substr(first, last - first + 1);
+}
+
+}  // namespace rtc