Modify build scripts for ios .framework to compile metal shaders.

webrtc/sdk/BUILD.gn

Index: webrtc/sdk/BUILD.gn
diff --git a/webrtc/sdk/BUILD.gn b/webrtc/sdk/BUILD.gn
index 3e44f9b4a33c4a3d569369e970f9a16056e8e707..15bcb9e9ccd32205eab216041e790bf4514311f6 100644
--- a/webrtc/sdk/BUILD.gn
+++ b/webrtc/sdk/BUILD.gn
@@ -7,6 +7,7 @@
 # be found in the AUTHORS file in the root of the source tree.
 
 import("../webrtc.gni")
+import("./objc/metal.gni")
 if (is_ios) {
   import("//build/config/ios/rules.gni")
 }
@@ -67,7 +68,11 @@ if (is_ios || is_mac) {
         "objc/Framework/Headers/WebRTC/RTCCameraPreviewView.h",
         "objc/Framework/Headers/WebRTC/UIDevice+RTCDevice.h",
       ]
-      libs = [ "AVFoundation.framework" ]
+      libs = [
+        "AVFoundation.framework",
+        "Metal.framework",
+        "MetalKit.framework",
+      ]
     }
     if (!build_with_chromium) {
       sources += [
@@ -265,6 +270,21 @@ if (is_ios || is_mac) {
   }
 
   if (is_ios) {
+    compile_metal_lib("metal_lib") {
+      source = "objc/Framework/Classes/metal/Shaders.metal"
+    }
+
+    bundle_data("metal_bundle") {
+      public_deps = [
+        ":metal_lib",
+      ]
+      metal_sources = get_target_outputs(":metal_lib")
+      sources = metal_sources
+      outputs = [
+        "{{bundle_root_dir}}//rtc_shaders.metallib",
+      ]
+    }
+
     ios_framework_bundle("rtc_sdk_framework_objc") {
       info_plist = "objc/Framework/Info.plist"
       output_name = "WebRTC"
@@ -307,6 +327,8 @@ if (is_ios || is_mac) {
         "objc/Framework/Headers/WebRTC/RTCVideoTrack.h",
         "objc/Framework/Headers/WebRTC/UIDevice+RTCDevice.h",
         "objc/Framework/Headers/WebRTC/WebRTC.h",
+        "objc/Framework/Headers/WebRTC/RTCMTLRenderer.h",
+        "objc/Framework/Headers/WebRTC/RTCMTLVideoView.h",
       ]
 
       sources = common_objc_headers
@@ -324,6 +346,7 @@ if (is_ios || is_mac) {
       ]
 
       deps = [
+        ":metal_bundle",
         ":rtc_sdk_peerconnection_objc",
         "../system_wrappers:field_trial_default",
         "../system_wrappers:metrics_default",
@@ -336,6 +359,8 @@ if (is_ios || is_mac) {
         "CoreMedia.framework",
         "GLKit.framework",
         "VideoToolbox.framework",
+        "Metal.framework",
+        "MetalKit.framework",
       ]
 
       configs += [