Move array_view.h to webrtc/api/

webrtc/api/array_view.h

Index: webrtc/api/array_view.h
diff --git a/webrtc/rtc_base/array_view.h b/webrtc/api/array_view.h
similarity index 92%
copy from webrtc/rtc_base/array_view.h
copy to webrtc/api/array_view.h
index afc69995ae8d9cbc1cd72a56c28a78326549d964..c97d388cc947d327b808efcc113b99a037a85108 100644
--- a/webrtc/rtc_base/array_view.h
+++ b/webrtc/api/array_view.h
@@ -8,14 +8,20 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#ifndef WEBRTC_RTC_BASE_ARRAY_VIEW_H_
-#define WEBRTC_RTC_BASE_ARRAY_VIEW_H_
+#ifndef WEBRTC_API_ARRAY_VIEW_H_
+#define WEBRTC_API_ARRAY_VIEW_H_
+
+#include <algorithm>
+#include <type_traits>
 
 #include "webrtc/rtc_base/checks.h"
 #include "webrtc/rtc_base/type_traits.h"
 
 namespace rtc {
 
+// tl;dr: rtc::ArrayView is the same thing as gsl::span from the Guideline
+//        Support Library.
+//
 // Many functions read from or write to arrays. The obvious way to do this is
 // to use two arguments, a pointer to the first element and an element count:
 //
@@ -155,7 +161,8 @@ class ArrayView final : public impl::ArrayViewBase<T, Size> {
   // Construct an empty ArrayView. Note that fixed-size ArrayViews of size > 0
   // cannot be empty.
   ArrayView() : ArrayView(nullptr, 0) {}
-  ArrayView(std::nullptr_t) : ArrayView() {}
+  ArrayView(std::nullptr_t)  // NOLINT
+      : ArrayView() {}
   ArrayView(std::nullptr_t, size_t size)
       : ArrayView(static_cast<T*>(nullptr), size) {
     static_assert(Size == 0 || Size == impl::kArrayViewVarSize, "");
@@ -164,7 +171,8 @@ class ArrayView final : public impl::ArrayViewBase<T, Size> {
 
   // Construct an ArrayView from an array.
   template <typename U, size_t N>
-  ArrayView(U (&array)[N]) : ArrayView(array, N) {
+  ArrayView(U (&array)[N])  // NOLINT
+      : ArrayView(array, N) {
     static_assert(Size == N || Size == impl::kArrayViewVarSize,
                   "Array size must match ArrayView size");
   }
@@ -176,11 +184,12 @@ class ArrayView final : public impl::ArrayViewBase<T, Size> {
   // N>, but not the other way around. We also don't allow conversion from
   // ArrayView<T> to ArrayView<T, N>, or from ArrayView<T, M> to ArrayView<T,
   // N> when M != N.
-  template <typename U,
-            typename std::enable_if<
-                Size != impl::kArrayViewVarSize &&
-                HasDataAndSize<U, T>::value>::type* = nullptr>
-  ArrayView(U& u) : ArrayView(u.data(), u.size()) {
+  template <
+      typename U,
+      typename std::enable_if<Size != impl::kArrayViewVarSize &&
+                              HasDataAndSize<U, T>::value>::type* = nullptr>
+  ArrayView(U& u)  // NOLINT
+      : ArrayView(u.data(), u.size()) {
     static_assert(U::size() == Size, "Sizes must match exactly");
   }
 
@@ -199,7 +208,8 @@ class ArrayView final : public impl::ArrayViewBase<T, Size> {
       typename U,
       typename std::enable_if<Size == impl::kArrayViewVarSize &&
                               HasDataAndSize<U, T>::value>::type* = nullptr>
-  ArrayView(U& u) : ArrayView(u.data(), u.size()) {}
+  ArrayView(U& u)  // NOLINT
+      : ArrayView(u.data(), u.size()) {}
 
   // Indexing and iteration. These allow mutation even if the ArrayView is
   // const, because the ArrayView doesn't own the array. (To prevent mutation,
@@ -250,4 +260,4 @@ inline ArrayView<T> MakeArrayView(T* data, size_t size) {
 
 }  // namespace rtc
 
-#endif  // WEBRTC_RTC_BASE_ARRAY_VIEW_H_
+#endif  // WEBRTC_API_ARRAY_VIEW_H_