Move optional.h to webrtc/api/
We use Optional in our public API, so its header should be in
webrtc/api/.
BUG=webrtc:8205
Review-Url: https://codereview.webrtc.org/3011943002
Cr-Commit-Position: refs/heads/master@{#19693}
diff --git a/webrtc/modules/audio_processing/BUILD.gn b/webrtc/modules/audio_processing/BUILD.gn
index e0719b4..4887250 100644
--- a/webrtc/modules/audio_processing/BUILD.gn
+++ b/webrtc/modules/audio_processing/BUILD.gn
@@ -238,6 +238,7 @@
"..:module_api",
"../..:webrtc_common",
"../../api:array_view",
+ "../../api:optional",
"../../audio/utility:audio_frame_operations",
"../../rtc_base:gtest_prod",
"../../rtc_base:protobuf_utils",
@@ -553,6 +554,7 @@
"..:module_api",
"../..:webrtc_common",
"../../api:array_view",
+ "../../api:optional",
"../../common_audio:common_audio",
"../../rtc_base:gtest_prod",
"../../rtc_base:protobuf_utils",
@@ -747,6 +749,7 @@
":audioproc_debug_proto",
":audioproc_protobuf_utils",
":audioproc_test_utils",
+ "../../api:optional",
"../../common_audio:common_audio",
"../../rtc_base:protobuf_utils",
"../../rtc_base:rtc_base_approved",
@@ -778,6 +781,7 @@
":audio_processing",
"..:module_api",
"../../api:array_view",
+ "../../api:optional",
"../../common_audio",
"../../rtc_base:rtc_base_approved",
"../../system_wrappers:system_wrappers",