[infra] Translate _sources.gypi files to _sources.gni files

third_party/tcmalloc/BUILD.gn

Index: third_party/tcmalloc/BUILD.gn
diff --git a/third_party/tcmalloc/BUILD.gn b/third_party/tcmalloc/BUILD.gn
index c1b9f102ed4a7d915e9063a5f4b9cafde3bee1e3..42073e29e233488d9d5afff602427759a57df58d 100644
--- a/third_party/tcmalloc/BUILD.gn
+++ b/third_party/tcmalloc/BUILD.gn
@@ -2,6 +2,8 @@
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
+import("tcmalloc_sources.gni")
+
 config("internal_config") {
   visibility = [ ":*" ]  # Only targets in this file can depend on this.
   cflags = [
@@ -62,11 +64,6 @@ source_set("dynamic_annotations") {
   ]
 }
 
-tcmalloc_sources_list = exec_script("../../tools/gypi_to_gn.py",
-                                    [ rebase_path("tcmalloc_sources.gypi") ],
-                                    "scope",
-                                    [ "tcmalloc_sources.gypi" ])
-
 source_set("tcmalloc") {
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [ ":internal_config" ]
@@ -128,5 +125,5 @@ source_set("tcmalloc") {
                                   "gperftools/src/profiler.cc",
                                 ])
 
-  sources = tcmalloc_sources_list.sources
+  sources = tcmalloc_sources
 }