Convert third_party source sets to static libraries.

third_party/libwebp/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/arm.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 
 config("libwebp_config") {
   include_dirs = [ "." ]
 }
 
 set_opt_level =
     !is_debug && is_posix && (current_cpu == "arm" || current_cpu == "arm64")
 
 use_dsp_neon =
     current_cpu == "arm64" || (current_cpu == "arm" && arm_version >= 7 &&
                                (arm_use_neon || arm_optionally_use_neon))
 
-source_set("libwebp_dec") {
+static_library("libwebp_dec") {
   sources = [
     "dec/alpha.c",
     "dec/buffer.c",
     "dec/frame.c",
     "dec/idec.c",
     "dec/io.c",
     "dec/quant.c",
     "dec/tree.c",
     "dec/vp8.c",
     "dec/vp8l.c",
@@ skipping 10 matching lines @@
   deps = [
     ":libwebp_dsp",
     ":libwebp_utils",
   ]
   all_dependent_configs = [ ":libwebp_config" ]
   if (use_dsp_neon) {
     deps += [ ":libwebp_dsp_neon" ]
   }
 }
 
-source_set("libwebp_demux") {
+static_library("libwebp_demux") {
   sources = [
     "demux/demux.c",
   ]
   all_dependent_configs = [ ":libwebp_config" ]
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":libwebp_utils",
   ]
 }
 
-source_set("libwebp_dsp") {
+static_library("libwebp_dsp") {
   sources = [
     "dsp/alpha_processing.c",
     "dsp/alpha_processing_mips_dsp_r2.c",
     "dsp/argb.c",
     "dsp/argb_mips_dsp_r2.c",
     "dsp/cost.c",
     "dsp/cost_mips32.c",
     "dsp/cost_mips_dsp_r2.c",
     "dsp/cpu.c",
     "dsp/dec.c",
@@ skipping 40 matching lines @@
     configs += [ "//build/config/android:no_cygprofile_instrumentation" ]
   }
   if (current_cpu == "x86" || current_cpu == "x64") {
     defines = [
       "WEBP_HAVE_SSE2",
       "WEBP_HAVE_SSE41",
     ]
   }
 }
 
-source_set("libwebp_dsp_sse41") {
+static_library("libwebp_dsp_sse41") {
   sources = [
     "dsp/alpha_processing_sse41.c",
     "dsp/dec_sse41.c",
     "dsp/enc_sse41.c",
     "dsp/lossless_enc_sse41.c",
   ]
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [ "//build/config/compiler:no_chromium_code" ]
   if (set_opt_level) {
     configs -= [ "//build/config/compiler:default_optimization" ]
     configs += [ "//build/config/compiler:optimize_max" ]
   }
 
   all_dependent_configs = [ ":libwebp_config" ]
   if (!is_msan) {
     if ((current_cpu == "x86" || current_cpu == "x64") &&
         (!is_win || is_clang)) {
       cflags = [ "-msse4.1" ]
     }
   }
 }
 
-source_set("libwebp_dsp_sse2") {
+static_library("libwebp_dsp_sse2") {
   sources = [
     "dsp/alpha_processing_sse2.c",
     "dsp/argb_sse2.c",
     "dsp/cost_sse2.c",
     "dsp/dec_sse2.c",
     "dsp/enc_sse2.c",
     "dsp/filters_sse2.c",
     "dsp/lossless_enc_sse2.c",
     "dsp/lossless_sse2.c",
     "dsp/rescaler_sse2.c",
@@ skipping 10 matching lines @@
   all_dependent_configs = [ ":libwebp_config" ]
   if (!is_msan) {
     if ((current_cpu == "x86" || current_cpu == "x64") &&
         (!is_win || is_clang)) {
       cflags = [ "-msse2" ]
     }
   }
 }
 
 if (use_dsp_neon) {
-  source_set("libwebp_dsp_neon") {
+  static_library("libwebp_dsp_neon") {
     sources = [
       "dsp/dec_neon.c",
       "dsp/enc_neon.c",
       "dsp/lossless_enc_neon.c",
       "dsp/lossless_neon.c",
       "dsp/rescaler_neon.c",
       "dsp/upsampling_neon.c",
     ]
 
     include_dirs = [ "." ]
@@ skipping 12 matching lines @@
       cflags = [ "-frename-registers" ]
     }
 
     if (is_android) {
       configs -= [ "//build/config/android:default_cygprofile_instrumentation" ]
       configs += [ "//build/config/android:no_cygprofile_instrumentation" ]
     }
   }
 }  # use_dsp_neon
 
-source_set("libwebp_enc") {
+static_library("libwebp_enc") {
   sources = [
     "enc/alpha.c",
     "enc/analysis.c",
     "enc/backward_references.c",
     "enc/config.c",
     "enc/cost.c",
     "enc/delta_palettization.c",
     "enc/filter.c",
     "enc/frame.c",
     "enc/histogram.c",
@@ skipping 25 matching lines @@
   ]
 }
 
 config("libwebp_utils_warnings") {
   if (is_clang) {
     # See https://code.google.com/p/webp/issues/detail?id=253.
     cflags = [ "-Wno-incompatible-pointer-types" ]
   }
 }
 
-source_set("libwebp_utils") {
+static_library("libwebp_utils") {
   sources = [
     "utils/bit_reader.c",
     "utils/bit_writer.c",
     "utils/color_cache.c",
     "utils/filters.c",
     "utils/huffman.c",
     "utils/huffman_encode.c",
     "utils/quant_levels.c",
     "utils/quant_levels_dec.c",
     "utils/random.c",
@@ skipping 19 matching lines @@
     ":libwebp_demux",
     ":libwebp_dsp",
     ":libwebp_enc",
     ":libwebp_utils",
   ]
   public_configs = [ ":libwebp_config" ]
   if (use_dsp_neon) {
     deps += [ ":libwebp_dsp_neon" ]
   }
 }