[stdlib] Rename "PrivateDarwin" to "PrivateLibc"

SwiftPrivateDarwinExtras is used by non-Darwin platforms as well; its
name is misleading. Rename it to SwiftPrivateLibcExtras, which is
closer to its actual function.

Author: modocache

stdlib/private/CMakeLists.txt

@@ -10,14 +10,14 @@ if(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
     add_subdirectory(StdlibUnittest)
     add_subdirectory(StdlibCollectionUnittest)
     add_subdirectory(StdlibUnittestFoundationExtras)
-    add_subdirectory(SwiftPrivateDarwinExtras)
+    add_subdirectory(SwiftPrivateLibcExtras)
     add_subdirectory(SwiftPrivatePthreadExtras)
   endif()
 endif()
 
 if(CMAKE_SYSTEM_NAME STREQUAL "Linux" OR CMAKE_SYSTEM_NAME STREQUAL "FreeBSD")
   add_subdirectory(StdlibUnittest)
   add_subdirectory(StdlibCollectionUnittest)
-  add_subdirectory(SwiftPrivateDarwinExtras)
+  add_subdirectory(SwiftPrivateLibcExtras)
   add_subdirectory(SwiftPrivatePthreadExtras)
 endif()

stdlib/private/StdlibUnittest/CMakeLists.txt

@@ -1,6 +1,6 @@
 set(swift_stdlib_unittest_platform_sources)
 set(swift_stdlib_unittest_module_depends
-  SwiftPrivate SwiftPrivatePthreadExtras SwiftPrivateDarwinExtras)
+  SwiftPrivate SwiftPrivatePthreadExtras SwiftPrivateLibcExtras)
 set(swift_stdlib_unittest_framework_depends)
 set(swift_stdlib_unittest_private_link_libraries)
 set(swift_stdlib_unittest_compile_flags)

stdlib/private/StdlibUnittest/StdlibCoreExtras.swift

@@ -11,7 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 import SwiftPrivate
-import SwiftPrivateDarwinExtras
+import SwiftPrivateLibcExtras
 #if os(OSX) || os(iOS)
 import Darwin
 #elseif os(Linux) || os(FreeBSD)

stdlib/private/StdlibUnittest/StdlibUnittest.swift.gyb

@@ -12,7 +12,7 @@
 
 import SwiftPrivate
 import SwiftPrivatePthreadExtras
-import SwiftPrivateDarwinExtras
+import SwiftPrivateLibcExtras
 
 #if os(OSX) || os(iOS) || os(watchOS) || os(tvOS)
 import Darwin

stdlib/private/SwiftPrivateDarwinExtras/CMakeLists.txt renamed to stdlib/private/SwiftPrivateLibcExtras/CMakeLists.txt

@@ -9,10 +9,10 @@ elseif(SWIFT_HOST_VARIANT STREQUAL "linux" OR SWIFT_HOST_VARIANT STREQUAL "freeb
     Glibc)
 endif()
 
-add_swift_library(swiftSwiftPrivateDarwinExtras SHARED IS_STDLIB
+add_swift_library(swiftSwiftPrivateLibcExtras SHARED IS_STDLIB
   # This file should be listed the first.  Module name is inferred from the
   # filename.
-  SwiftPrivateDarwinExtras.swift
+  SwiftPrivateLibcExtras.swift
   Subprocess.swift
 
   SWIFT_MODULE_DEPENDS ${swift_private_darwin_extras_module_depends}

stdlib/private/SwiftPrivateDarwinExtras/Subprocess.swift renamed to stdlib/private/SwiftPrivateLibcExtras/Subprocess.swift

@@ -1,4 +1,4 @@
-//===--- SwiftPrivateDarwinExtras.swift -----------------------------------===//
+//===--- SwiftPrivateLibcExtras.swift -----------------------------------===//
 //
 // This source file is part of the Swift.org open source project
 //