Do not build task_queue.cc and include from webrtc_overrides in Chrome.

webrtc/base/BUILD.gn

Index: webrtc/base/BUILD.gn
diff --git a/webrtc/base/BUILD.gn b/webrtc/base/BUILD.gn
index ed40a42280fab33fdcb009aa6ca05233b6a962d9..6a2bc9ddd18919d6b0ce65a139d8e5c17d5c6562 100644
--- a/webrtc/base/BUILD.gn
+++ b/webrtc/base/BUILD.gn
@@ -201,31 +201,41 @@ static_library("rtc_task_queue") {
     "sequenced_task_checker.h",
     "sequenced_task_checker_impl.cc",
     "sequenced_task_checker_impl.h",
-    "task_queue.h",
-    "task_queue_posix.h",
   ]
 
-  if (rtc_build_libevent) {
-    deps = [
-      "//base/third_party/libevent",
-    ]
-  }
-
-  if (rtc_enable_libevent) {
+  if (build_with_chromium) {
     sources += [
-      "task_queue_libevent.cc",
-      "task_queue_posix.cc",
+      "../../webrtc_overrides/webrtc/base/task_queue.cc",
+      "../../webrtc_overrides/webrtc/base/task_queue.h",
     ]
-    all_dependent_configs = [ ":enable_libevent_config" ]
+    include_dirs = [ "../../webrtc_overrides" ]
   } else {
-    if (is_mac || is_ios) {
+    sources += [
+      "task_queue.h",
+      "task_queue_posix.h",
+    ]
+    if (rtc_build_libevent) {
+      deps = [
+        "//base/third_party/libevent",
+      ]
+    }
+
+    if (rtc_enable_libevent) {
       sources += [
-        "task_queue_gcd.cc",
+        "task_queue_libevent.cc",
         "task_queue_posix.cc",
       ]
-    }
-    if (is_win) {
-      sources += [ "task_queue_win.cc" ]
+      all_dependent_configs = [ ":enable_libevent_config" ]
+    } else {
+      if (is_mac || is_ios) {
+        sources += [
+          "task_queue_gcd.cc",
+          "task_queue_posix.cc",
+        ]
+      }
+      if (is_win) {
+        sources += [ "task_queue_win.cc" ]
+      }
     }
   }
 }