Convert GN single-item list concat to use lists.

tools/gn/secondary/third_party/leveldatabase/BUILD.gn

 # Copyright (c) 2013 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.
 
 # Snappy is a compression library we use.
 # TODO(brettw) It's not clear why this needs to be parameterized.
 use_snappy = true
 
 defines = [ "LEVELDB_PLATFORM_CHROMIUM=1" ]
 
 config("leveldatabase_config") {
   include_dirs = [
     ".",
     "src",
     "src/include",
   ]
   if (is_win) {
-    include_dirs += "src/port/win"
+    include_dirs += [ "src/port/win" ]
   }
 }
 
 static_library("leveldatabase") {
   external = true
   sources = [
     "env_chromium.cc",
     "env_chromium.h",
     "env_idb.h",
     "port/port_chromium.cc",
@@ skipping 74 matching lines @@
     "src/util/hash.cc",
     "src/util/hash.h",
     "src/util/logging.cc",
     "src/util/logging.h",
     "src/util/mutexlock.h",
     "src/util/options.cc",
     "src/util/random.h",
     "src/util/status.cc",
   ]
 
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
 
   direct_dependent_configs = [ ":leveldatabase_config" ]
 
   deps = [
     "//base",
     "//base/third_party/dynamic_annotations",
     "//third_party/re2",
   ]
 
   if (use_snappy) {
-    defines += "USE_SNAPPY=1"
-    deps += "//third_party/snappy"
+    defines += [ "USE_SNAPPY=1" ]
+    deps += [ "//third_party/snappy" ]
   }
 }
 
 test("env_chromium_unittests") {
   sources = [
     "env_chromium_unittest.cc",
   ]
   deps = [
     ":leveldatabase",
     "//base/test:test_support_base",
     "//testing/gtest",
   ]
 }
 
 static_library("leveldb_testutil") {
   sources = [
     "src/util/histogram.cc",
     "src/util/histogram.h",
     "src/util/testharness.cc",
     "src/util/testharness.h",
     "src/util/testutil.cc",
     "src/util/testutil.h",
   ]
 
   forward_dependent_configs_from = [ ":leveldatabase" ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
 
   deps = [
     ":leveldatabase",
     "//base",
   ]
 }
 
 test("leveldb_arena_test") {
   sources = [
     "src/util/arena_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_bloom_test") {
   sources = [
     "src/util/bloom_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_cache_test") {
   sources = [
     "src/util/cache_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_corruption_test") {
   sources = [
     "src/db/corruption_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_crc32c_test") {
   sources = [
     "src/util/crc32c_test.cc"
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_db_bench") {
   sources = [
     "src/db/db_bench.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_db_test") {
   sources = [
     "src/db/db_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_dbformat_test") {
   sources = [
     "src/db/dbformat_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_env_test") {
   sources = [
     "src/util/env_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_filename_test") {
   sources = [
     "src/db/filename_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_filter_block_test") {
   sources = [
     "src/table/filter_block_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_log_test") {
   sources = [
     "src/db/log_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_skiplist_test") {
   sources = [
     "src/db/skiplist_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_table_test") {
   sources = [
     "src/table/table_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_version_edit_test") {
   sources = [
     "src/db/version_edit_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }
 
 test("leveldb_write_batch_test") {
   sources = [
     "src/db/write_batch_test.cc",
   ]
-  configs -= "//build/config/compiler:chromium_code"
-  configs += "//build/config/compiler:no_chromium_code"
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
   deps = [
     ":leveldb_testutil",
   ]
 }