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/system_wrappers/source/rw_lock_win.cc

@@ -0,0 +1,97 @@
+/*
+ *  Copyright (c) 2012 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/system_wrappers/source/rw_lock_win.h"
+
+#include "webrtc/system_wrappers/interface/trace.h"
+
+namespace webrtc {
+
+static bool native_rw_locks_supported = false;
+static bool module_load_attempted = false;
+static HMODULE library = NULL;
+
+typedef void (WINAPI* InitializeSRWLock)(PSRWLOCK);
+
+typedef void (WINAPI* AcquireSRWLockExclusive)(PSRWLOCK);
+typedef void (WINAPI* ReleaseSRWLockExclusive)(PSRWLOCK);
+
+typedef void (WINAPI* AcquireSRWLockShared)(PSRWLOCK);
+typedef void (WINAPI* ReleaseSRWLockShared)(PSRWLOCK);
+
+InitializeSRWLock       initialize_srw_lock;
+AcquireSRWLockExclusive acquire_srw_lock_exclusive;
+AcquireSRWLockShared    acquire_srw_lock_shared;
+ReleaseSRWLockShared    release_srw_lock_shared;
+ReleaseSRWLockExclusive release_srw_lock_exclusive;
+
+RWLockWin::RWLockWin() {
+  initialize_srw_lock(&lock_);
+}
+
+RWLockWin* RWLockWin::Create() {
+  if (!LoadModule()) {
+    return NULL;
+  }
+  return new RWLockWin();
+}
+
+void RWLockWin::AcquireLockExclusive() {
+  acquire_srw_lock_exclusive(&lock_);
+}
+
+void RWLockWin::ReleaseLockExclusive() {
+  release_srw_lock_exclusive(&lock_);
+}
+
+void RWLockWin::AcquireLockShared() {
+  acquire_srw_lock_shared(&lock_);
+}
+
+void RWLockWin::ReleaseLockShared() {
+  release_srw_lock_shared(&lock_);
+}
+
+bool RWLockWin::LoadModule() {
+  if (module_load_attempted) {
+    return native_rw_locks_supported;
+  }
+  module_load_attempted = true;
+  // Use native implementation if supported (i.e Vista+)
+  library = LoadLibrary(TEXT("Kernel32.dll"));
+  if (!library) {
+    return false;
+  }
+  WEBRTC_TRACE(kTraceStateInfo, kTraceUtility, -1, "Loaded Kernel.dll");
+
+  initialize_srw_lock =
+    (InitializeSRWLock)GetProcAddress(library, "InitializeSRWLock");
+
+  acquire_srw_lock_exclusive =
+    (AcquireSRWLockExclusive)GetProcAddress(library,
+                                            "AcquireSRWLockExclusive");
+  release_srw_lock_exclusive =
+    (ReleaseSRWLockExclusive)GetProcAddress(library,
+                                            "ReleaseSRWLockExclusive");
+  acquire_srw_lock_shared =
+    (AcquireSRWLockShared)GetProcAddress(library, "AcquireSRWLockShared");
+  release_srw_lock_shared =
+    (ReleaseSRWLockShared)GetProcAddress(library, "ReleaseSRWLockShared");
+
+  if (initialize_srw_lock && acquire_srw_lock_exclusive &&
+      release_srw_lock_exclusive && acquire_srw_lock_shared &&
+      release_srw_lock_shared) {
+    WEBRTC_TRACE(kTraceStateInfo, kTraceUtility, -1, "Loaded Native RW Lock");
+    native_rw_locks_supported = true;
+  }
+  return native_rw_locks_supported;
+}
+
+}  // namespace webrtc