Make devtools use common generated blink source directory instead of gen/webkit.

content/browser/devtools/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("//tools/grit/grit_rule.gni")
 
 # In GYP: devtools_resources target.
 group("resources") {
   deps = [
     ":devtools_resources",
     ":devtools_protocol_handler",
   ]
 }
 
 # In GYP: devtools_resources action in the devtools_resources target.
 grit("devtools_resources") {
   source = "$root_gen_dir/devtools/devtools_resources.grd"
 
   # TOOD(brettw) remove this so the output file goes into the target_gen_dir,
   # but keep this for not for GYP compat.
-  output_dir = "$root_gen_dir/webkit"
+  output_dir = "$root_gen_dir/blink"
   outputs = [
     "grit/devtools_resources.h",
     "devtools_resources.pak",
     "grit/devtools_resources_map.cc",
     "grit/devtools_resources_map.h",
   ]
 
   defines =
       [ "SHARED_INTERMEDIATE_DIR=" + rebase_path(root_gen_dir, root_build_dir) ]
 
@@ skipping 22 matching lines @@
   ]
 
   args =
       rebase_path(inputs, root_build_dir) + rebase_path(outputs, root_build_dir)
 }
 
 source_set("devtools_protocol_handler") {
   visibility = [ ":resources" ]
   sources = get_target_outputs(":gen_devtools_protocol_handler")
 }