Add BUILD.gn for //media/ffmpeg

media/base/BUILD.gn

 # Copyright 2014 The Chromium 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/android/config.gni")
 import("//build/config/arm.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//build/config/linux/pkg_config.gni")
 import("//media/media_options.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 
+config("base_config") {
+  configs = [
+    # This target uses the ALLOCATOR_SHIM define.
+    "//base/allocator:allocator_shim_define",
+    "//build/config:precompiled_headers",
+    "//build/config/compiler:no_size_t_to_int_warning",
+    "//media:media_config",
+    "//media:media_implementation",
+  ]
+}
+
 source_set("base") {
   # This is part of the media component.
-  visibility = [
-    ":*",
-    "//media",
-    "//media/capture",
-  ]
+  visibility = [ "//media/*" ]
   sources = [
     "audio_block_fifo.cc",
     "audio_block_fifo.h",
     "audio_buffer.cc",
     "audio_buffer.h",
     "audio_buffer_converter.cc",
     "audio_buffer_converter.h",
     "audio_buffer_queue.cc",
     "audio_buffer_queue.h",
     "audio_capturer_source.h",
@@ skipping 212 matching lines @@
   deps = [
     "//base/third_party/dynamic_annotations:dynamic_annotations",
     "//gpu",
     "//media:media_features",
     "//media:shared_memory_support",
     "//skia",
     "//ui/events:events_base",
     "//url:url",
   ]
   libs = []
-  configs += [
-    # This target uses the ALLOCATOR_SHIM define.
-    "//base/allocator:allocator_shim_define",
-    "//build/config:precompiled_headers",
-    "//media:media_config",
-    "//media:media_implementation",
-  ]
+  configs += [ ":base_config" ]
 
   if (media_use_ffmpeg) {
     if (!is_android) {
       sources += [
         "audio_video_metadata_extractor.cc",
         "audio_video_metadata_extractor.h",
         "media_file_checker.cc",
         "media_file_checker.h",
       ]
     }
@@ skipping 38 matching lines @@
   if (current_cpu == "x86" || current_cpu == "x64") {
     sources += [
       "simd/convert_rgb_to_yuv_sse2.cc",
       "simd/convert_rgb_to_yuv_ssse3.cc",
       "simd/convert_yuv_to_rgb_x86.cc",
       "simd/filter_yuv_sse2.cc",
     ]
     deps += [ ":media_yasm" ]
   }
 
-  configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
-
   if (is_linux || is_win) {
     sources += [
       "keyboard_event_counter.cc",
       "keyboard_event_counter.h",
     ]
   }
 }
 
 # Minimal media component for media/cast on iOS.
 config("base_for_cast_ios_dependent_config") {
@@ skipping 268 matching lines @@
 
 fuzzer_test("media_container_names_fuzzer") {
   sources = [
     "container_names_fuzzertest.cc",
   ]
   deps = [
     "//base",
     "//media",
   ]
 }