[libpng] Migrate to new third party layout

Soft transition step 4 per:
https://fuchsia.dev/fuchsia-src/concepts/source_code/third-party-management

rm BUILD.gn README.fuchsia OWNERS

Change-Id: Iafd59260775b5bb900ab861b1698ccd4ca2f433f
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/libpng/+/622822
Reviewed-by: Jay Zhuang <jayzhuang@google.com>
diff --git a/BUILD.gn b/BUILD.gn
deleted file mode 100644
index 2f0ec68..0000000
--- a/BUILD.gn
+++ /dev/null
@@ -1,90 +0,0 @@
-# Copyright 2016 The Fuchsia Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import("//build/config/arm.gni")
-
-config("libpng_config") {
-  include_dirs = [ "." ]
-  defines = []
-}
-
-# Must be in a config because of how GN orders flags (otherwise -Wall will
-# appear after this, and turn it back on).
-config("clang_warnings") {
-  if (is_clang) {
-    cflags = [
-      "-Wno-conversion",
-      "-Wno-implicit-fallthrough",
-      "-Wno-sign-compare",
-
-      # libpng checks that the width is not greater than PNG_SIZE_MAX.
-      # On platforms where size_t is 64-bits, this comparison will always
-      # be false.
-      "-Wno-tautological-constant-out-of-range-compare",
-
-      "-Wno-unused-but-set-parameter",
-      "-Wno-unused-but-set-variable",
-    ]
-  }
-}
-
-source_set("libpng") {
-  sources = [
-    "png.c",
-    "png.h",
-    "pngconf.h",
-    "pngerror.c",
-    "pngget.c",
-    "pnginfo.h",
-    "pnglibconf.h",
-    "pngmem.c",
-    "pngpread.c",
-    "pngprefix.h",
-    "pngpriv.h",
-    "pngread.c",
-    "pngrio.c",
-    "pngrtran.c",
-    "pngrutil.c",
-    "pngset.c",
-    "pngstruct.h",
-    "pngtrans.c",
-    "pngwio.c",
-    "pngwrite.c",
-    "pngwtran.c",
-    "pngwutil.c",
-  ]
-  defines = []
-  cflags = []
-  if (current_cpu == "x86" || current_cpu == "x64") {
-    sources += [
-      "intel/filter_sse2_intrinsics.c",
-      "intel/intel_init.c",
-    ]
-    defines += [ "PNG_INTEL_SSE_OPT=1" ]
-  } else if ((current_cpu == "arm" || current_cpu == "arm64") && arm_use_neon) {
-    sources += [
-      "arm/arm_init.c",
-      "arm/filter_neon_intrinsics.c",
-      "arm/palette_neon_intrinsics.c",
-    ]
-    defines += [
-      "PNG_ARM_NEON_OPT=2",
-      "PNG_ARM_NEON_IMPLEMENTATION=1",
-    ]
-  }
-
-  public_configs = [ ":libpng_config" ]
-  public_deps = [ "//third_party/zlib" ]
-  configs += [ ":clang_warnings" ]
-
-  # TODO(fxbug.dev/77808): pull new code for libpng before we allow it to be
-  # used in more places.
-  visibility = [
-    "//src/camera/bin/factory/*",
-    "//src/ui/tools/gltf_export/*",
-    "//src/ui/examples/frame-compression/*",
-    "//src/developer/forensics/feedback_data/*",
-    "//third_party/freetype2/*",
-  ]
-}
diff --git a/OWNERS b/OWNERS
deleted file mode 100644
index f84548a..0000000
--- a/OWNERS
+++ /dev/null
@@ -1,3 +0,0 @@
-villarreald@google.com
-reveman@google.com
-guruji@google.com
diff --git a/README.fuchsia b/README.fuchsia
deleted file mode 100644
index 1435241..0000000
--- a/README.fuchsia
+++ /dev/null
@@ -1,24 +0,0 @@
-Name: libpng
-URL: http://libpng.org/
-Upstream Git: https://github.com/glennrp/libpng
-Version: 1.6.37
-Security Critical: yes
-License: libpng license
-License File: LICENSE
-License Android Compatible: yes
-Description:
-
-Updated to 1.6.37, stripped all unneeded files.
-
-- Strip all unneeded files
-  rm -r contrib projects scripts tests \
-        ANNOUNCE CHANGES INSTALL TODO autogen.sh configure.ac CMakeLists.txt Makefile.am \
-	aclocal.m4 compile config.guess config.sub configure depcomp install.sh ltmain.sh \
-	missing test-driver libpng-manual.txt \
-        *.in *.3 *.5 *.png *.jpg *.dfa
-
-- Use custom configuration file pnglibconf.h, which turns off all features that
-  are not in use.
-- Use custom prefix file pngprefix.h, which avoids namespace conflicts with
-  pdfium's copy of libpng.
-- Configures custom png chunk user limits (crbug.com/117369) in pnglibconf.h.