Actually move CoreVideoFrameBuffer from webrtc/common_video/ to webrtc/sdk/objc/

The previous reland https://codereview.webrtc.org/2860033002/ didn't
actually move CoreVideoFrameBuffer because of a rebase mistake. This CL
moves the files.

BUG=None

Review-Url: https://codereview.webrtc.org/2864303002
Cr-Commit-Position: refs/heads/master@{#18048}
diff --git a/webrtc/sdk/BUILD.gn b/webrtc/sdk/BUILD.gn
index 5596af0..fa44c48 100644
--- a/webrtc/sdk/BUILD.gn
+++ b/webrtc/sdk/BUILD.gn
@@ -212,6 +212,7 @@
     ]
 
     deps = [
+      ":rtc_sdk_corevideoframebuffer",
       ":webrtc_h264_video_toolbox",
       "../api:video_frame_api",
       "../base:rtc_base",
@@ -425,6 +426,20 @@
     ]
   }
 
+  rtc_static_library("rtc_sdk_corevideoframebuffer") {
+    sources = [
+      "objc/Framework/Classes/corevideo_frame_buffer.cc",
+      "objc/Framework/Classes/corevideo_frame_buffer.h",
+    ]
+
+    deps = [
+      "../base:rtc_base_approved",
+      "../common_video",
+    ]
+
+    libs = [ "CoreVideo.framework" ]
+  }
+
   rtc_static_library("webrtc_h264_video_toolbox") {
     sources = [
       "objc/Framework/Classes/h264_video_toolbox_decoder.cc",
@@ -439,6 +454,7 @@
 
     deps = [
       ":rtc_sdk_common_objc",
+      ":rtc_sdk_corevideoframebuffer",
       "../api:video_frame_api",
       "../base:rtc_base_approved",
       "../common_video",