Implement a runtime headless mode for Linux

chrome/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/buildflag_header.gni")
 import("//build/config/chrome_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/compiler/pgo/pgo.gni")
 import("//build/config/features.gni")
 import("//build/config/locales.gni")
@@ skipping 221 matching lines @@
       deps += [
         # On Linux, link the dependencies (libraries) that make up actual
         # Chromium functionality directly into the executable.
         ":browser_dependencies",
         ":child_dependencies",
         ":manpage",
 
         # Needed to use the master_preferences functions
         "//chrome/installer/util:with_no_strings",
         "//content/public/app:both",
+
+        # For headless mode.
+        "//headless:headless_shell_lib",
       ]
       if (enable_plugins && enable_pdf) {
         deps += [ "//pdf" ]
       }
 
       public_deps = [
         ":xdg_mime",  # Needs to be public for installer to consume files.
         "//chrome/common:features",
       ]
 
@@ skipping 1349 matching lines @@
       "//chrome/app/theme/$branding_path_component/product_logo_48.png",
       "//chrome/tools/build/linux/chrome-wrapper",
       "//third_party/xdg-utils/scripts/xdg-mime",
       "//third_party/xdg-utils/scripts/xdg-settings",
     ]
     outputs = [
       "$root_out_dir/{{source_file_part}}",
     ]
   }
 }