Revert of Moving webrtc.gni up one level from build/ (patchset #1 id:1 of https://codereview.webrtc.org/2651543003/ )

Reason for revert:
This was causing the following failure: https://build.chromium.org/p/chromium.webrtc.fyi/builders/Android%20Builder/builds/838/steps/generate_build_files/logs/stdio

Original issue's description:
> Moving webrtc.gni up one level from build/
>
> BUG=webrtc:7030
>
> Review-Url: https://codereview.webrtc.org/2651543003
> Cr-Commit-Position: refs/heads/master@{#16241}
> Committed: https://chromium.googlesource.com/external/webrtc/+/35a32700fc9b5d932ddbd528c12f59c3274e4774

TBR=kjellander@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:7030

Review-Url: https://codereview.webrtc.org/2657563002
Cr-Commit-Position: refs/heads/master@{#16244}
diff --git a/webrtc/modules/BUILD.gn b/webrtc/modules/BUILD.gn
index e44b35f..d87e7f9 100644
--- a/webrtc/modules/BUILD.gn
+++ b/webrtc/modules/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../webrtc.gni")
+import("../build/webrtc.gni")
 import("audio_coding/audio_coding.gni")
 
 group("modules") {
diff --git a/webrtc/modules/audio_coding/BUILD.gn b/webrtc/modules/audio_coding/BUILD.gn
index 4046373..044d57e 100644
--- a/webrtc/modules/audio_coding/BUILD.gn
+++ b/webrtc/modules/audio_coding/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 import("audio_coding.gni")
 import("//build/config/arm.gni")
 import("//third_party/protobuf/proto_library.gni")
diff --git a/webrtc/modules/audio_coding/audio_coding.gni b/webrtc/modules/audio_coding/audio_coding.gni
index 0f3a75f..13577f8 100644
--- a/webrtc/modules/audio_coding/audio_coding.gni
+++ b/webrtc/modules/audio_coding/audio_coding.gni
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 audio_codec_defines = []
 if (rtc_include_ilbc) {
diff --git a/webrtc/modules/audio_conference_mixer/BUILD.gn b/webrtc/modules/audio_conference_mixer/BUILD.gn
index 428bcac..b4705d5 100644
--- a/webrtc/modules/audio_conference_mixer/BUILD.gn
+++ b/webrtc/modules/audio_conference_mixer/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 config("audio_conference_mixer_config") {
   visibility = [ ":*" ]  # Only targets in this file can depend on this.
diff --git a/webrtc/modules/audio_device/BUILD.gn b/webrtc/modules/audio_device/BUILD.gn
index ac8fdbe..4dc6760 100644
--- a/webrtc/modules/audio_device/BUILD.gn
+++ b/webrtc/modules/audio_device/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
diff --git a/webrtc/modules/audio_mixer/BUILD.gn b/webrtc/modules/audio_mixer/BUILD.gn
index 083e02b..25c782b 100644
--- a/webrtc/modules/audio_mixer/BUILD.gn
+++ b/webrtc/modules/audio_mixer/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 group("audio_mixer") {
   public_deps = [
diff --git a/webrtc/modules/audio_processing/BUILD.gn b/webrtc/modules/audio_processing/BUILD.gn
index 87501f4..4f3ea13 100644
--- a/webrtc/modules/audio_processing/BUILD.gn
+++ b/webrtc/modules/audio_processing/BUILD.gn
@@ -8,7 +8,7 @@
 
 import("//build/config/arm.gni")
 import("//third_party/protobuf/proto_library.gni")
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 declare_args() {
   # Disables the usual mode where we trust the reported system delay
diff --git a/webrtc/modules/bitrate_controller/BUILD.gn b/webrtc/modules/bitrate_controller/BUILD.gn
index 58398f3..b2747db 100644
--- a/webrtc/modules/bitrate_controller/BUILD.gn
+++ b/webrtc/modules/bitrate_controller/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 rtc_static_library("bitrate_controller") {
   # TODO(mbonadei): Remove (bugs.webrtc.org/6828)
diff --git a/webrtc/modules/congestion_controller/BUILD.gn b/webrtc/modules/congestion_controller/BUILD.gn
index a20339c..03e0d5c 100644
--- a/webrtc/modules/congestion_controller/BUILD.gn
+++ b/webrtc/modules/congestion_controller/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 rtc_static_library("congestion_controller") {
   sources = [
diff --git a/webrtc/modules/desktop_capture/BUILD.gn b/webrtc/modules/desktop_capture/BUILD.gn
index 9c9a466..67ec8ce 100644
--- a/webrtc/modules/desktop_capture/BUILD.gn
+++ b/webrtc/modules/desktop_capture/BUILD.gn
@@ -7,7 +7,7 @@
 # be found in the AUTHORS file in the root of the source tree.
 
 import("//build/config/ui.gni")
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 use_desktop_capture_differ_sse2 = current_cpu == "x86" || current_cpu == "x64"
 
diff --git a/webrtc/modules/media_file/BUILD.gn b/webrtc/modules/media_file/BUILD.gn
index 32825af..8003cd8 100644
--- a/webrtc/modules/media_file/BUILD.gn
+++ b/webrtc/modules/media_file/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 config("media_file_config") {
   visibility = [ ":*" ]  # Only targets in this file can depend on this.
diff --git a/webrtc/modules/pacing/BUILD.gn b/webrtc/modules/pacing/BUILD.gn
index f94def7..0a357c0 100644
--- a/webrtc/modules/pacing/BUILD.gn
+++ b/webrtc/modules/pacing/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 rtc_static_library("pacing") {
   sources = [
diff --git a/webrtc/modules/remote_bitrate_estimator/BUILD.gn b/webrtc/modules/remote_bitrate_estimator/BUILD.gn
index 13e2382..81028f6 100644
--- a/webrtc/modules/remote_bitrate_estimator/BUILD.gn
+++ b/webrtc/modules/remote_bitrate_estimator/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 rtc_static_library("remote_bitrate_estimator") {
   # TODO(mbonadei): Remove (bugs.webrtc.org/6828)
diff --git a/webrtc/modules/rtp_rtcp/BUILD.gn b/webrtc/modules/rtp_rtcp/BUILD.gn
index 4fa4d49..9b23621 100644
--- a/webrtc/modules/rtp_rtcp/BUILD.gn
+++ b/webrtc/modules/rtp_rtcp/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 rtc_static_library("rtp_rtcp") {
   sources = [
diff --git a/webrtc/modules/utility/BUILD.gn b/webrtc/modules/utility/BUILD.gn
index ec11b9f..5b6a232 100644
--- a/webrtc/modules/utility/BUILD.gn
+++ b/webrtc/modules/utility/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 rtc_static_library("utility") {
   sources = [
diff --git a/webrtc/modules/video_capture/BUILD.gn b/webrtc/modules/video_capture/BUILD.gn
index 90b824a..6887552 100644
--- a/webrtc/modules/video_capture/BUILD.gn
+++ b/webrtc/modules/video_capture/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 # Note this target is missing an implementation for the video capture.
 # Targets must link with either 'video_capture' or
diff --git a/webrtc/modules/video_coding/BUILD.gn b/webrtc/modules/video_coding/BUILD.gn
index 5750d10..f84936a 100644
--- a/webrtc/modules/video_coding/BUILD.gn
+++ b/webrtc/modules/video_coding/BUILD.gn
@@ -6,7 +6,7 @@
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 rtc_static_library("video_coding") {
   sources = [
diff --git a/webrtc/modules/video_processing/BUILD.gn b/webrtc/modules/video_processing/BUILD.gn
index 6da43b4..5da0ae8 100644
--- a/webrtc/modules/video_processing/BUILD.gn
+++ b/webrtc/modules/video_processing/BUILD.gn
@@ -7,7 +7,7 @@
 # be found in the AUTHORS file in the root of the source tree.
 
 import("//build/config/arm.gni")
-import("../../webrtc.gni")
+import("../../build/webrtc.gni")
 
 build_video_processing_sse2 = current_cpu == "x86" || current_cpu == "x64"