Remove the enable_task_manager build flag and define.

chrome/browser/extensions/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//chrome/common/features.gni")
 import("//extensions/features/features.gni")
 import("//media/media_options.gni")
 
@@ skipping 1032 matching lines @@
     if (use_x11) {
       configs += [ "//build/config/linux:x11" ]
       deps += [
         "//ui/events:events_base",
         "//ui/events/platform",
         "//ui/events/platform/x11",
       ]
     }
   }
 
-  if (!is_android && !is_ios) {
-    # Non-mobile.
-    #deps += [ "//apps" ]
+  if (!is_android) {
+    sources += [
+      "api/processes/processes_api.cc",
+      "api/processes/processes_api.h",
+    ]
   }
 
   if (is_win || is_mac) {
     sources += [
       "api/networking_private/crypto_verify_impl.cc",
       "api/networking_private/crypto_verify_impl.h",
       "api/networking_private/networking_private_credentials_getter.h",
       "api/networking_private/networking_private_credentials_getter_mac.cc",
       "api/networking_private/networking_private_credentials_getter_win.cc",
     ]
@@ skipping 67 matching lines @@
       "api/mdns/dns_sd_delegate.h",
       "api/mdns/dns_sd_device_lister.cc",
       "api/mdns/dns_sd_device_lister.h",
       "api/mdns/dns_sd_registry.cc",
       "api/mdns/dns_sd_registry.h",
       "api/mdns/mdns_api.cc",
       "api/mdns/mdns_api.h",
     ]
   }
 
-  if (enable_task_manager) {
-    sources += [
-      "api/processes/processes_api.cc",
-      "api/processes/processes_api.h",
-    ]
-  }
-
   if (enable_rlz_support) {
     deps += [ "//rlz:rlz_lib" ]
   }
 
   if (enable_webrtc) {
     sources += [ "api/webrtc_logging_private/webrtc_logging_private_api.cc" ]
   } else {
     sources +=
         [ "api/webrtc_logging_private/webrtc_logging_private_api_stub.cc" ]
   }
@@ skipping 25 matching lines @@
       "api/braille_display_private/brlapi_connection.cc",
       "api/braille_display_private/brlapi_connection.h",
       "api/braille_display_private/brlapi_keycode_map.cc",
       "api/braille_display_private/brlapi_keycode_map.h",
     ]
     deps += [ "//build/linux/libbrlapi" ]
   } else {
     sources += [ "api/braille_display_private/braille_controller_stub.cc" ]
   }
 }