GN: Define GN var to use new IDL compiler for dictionary

Also updates some BUILD.gn files to stop the current IDL compiler
generate code of dictionaries, if |use_idl_compiler_v2_for_dictionary|
is set true in gn.args.


Bug: 839389
Change-Id: I69bd10cf4e7f57cd1d9873c4b2202a917ed67ba5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1969318
Commit-Queue: Hitoshi Yoshida <peria@chromium.org>
Reviewed-by: Yuki Shiino <yukishiino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#725448}

third_party/blink/renderer/bindings/bindings.gni

@@ -7,6 +7,12 @@
 
 import("//third_party/blink/renderer/bindings/modules/v8/v8.gni")
 
+declare_args() {
+  # If this variable is set true, we use a new code generator to generate code
+  # of IDL dictionaries.  See https://crbug.com/839389 for the details.
+  use_v8_bind_gen_for_dictionary = false
+}
+
 bindings_core_v8_files =
     get_path_info([
                     "core/v8/active_script_wrappable.cc",

third_party/blink/renderer/bindings/core/v8/BUILD.gn

@@ -202,9 +202,13 @@ if (is_win && is_official_build) {
   bindings_core_generated_interface_files =
       [ "$bindings_core_v8_output_dir/v8_generated_core_bindings.cc" ]
 } else {
+  _core_definition_idl_files = core_definition_idl_files
+  if (use_v8_bind_gen_for_dictionary) {
+    _core_definition_idl_files -= core_dictionary_idl_files
+  }
   bindings_core_generated_interface_files =
       process_file_template(
-          core_definition_idl_files,
+          _core_definition_idl_files,
           [
             "$bindings_core_v8_output_dir/v8_{{source_name_part}}.cc",
             "$bindings_core_v8_output_dir/v8_{{source_name_part}}.h",
@@ -227,6 +231,9 @@ group("bindings_core_v8_generated") {
 idl_compiler("generate_bindings_core_v8_interfaces") {
   sources = core_definition_idl_files + core_testing_definition_idl_files +
             generated_webcore_testing_idl_files
+  if (use_v8_bind_gen_for_dictionary) {
+    sources -= core_dictionary_idl_files
+  }
   output_dir = bindings_core_v8_output_dir
   output_name_suffix = ""
   target_component = "core"
@@ -234,6 +241,9 @@ idl_compiler("generate_bindings_core_v8_interfaces") {
 
 aggregate_generated_bindings("generate_bindings_core_v8_all_interfaces") {
   sources = core_definition_idl_files
+  if (use_v8_bind_gen_for_dictionary) {
+    sources -= core_dictionary_idl_files
+  }
   outputs = [
     "$bindings_core_v8_output_dir/v8_generated_core_bindings.cc",
   ]
@@ -244,7 +254,11 @@ aggregate_generated_bindings("generate_bindings_core_v8_all_interfaces") {
 }
 
 idl_impl("bindings_core_impl_generated") {
-  dict_idls = core_dictionary_idl_files + core_testing_dictionary_idl_files
+  if (use_v8_bind_gen_for_dictionary) {
+    dict_idls = []
+  } else {
+    dict_idls = core_dictionary_idl_files + core_testing_dictionary_idl_files
+  }
   non_dict_outputs = bindings_core_generated_union_type_files +
                      generated_core_testing_callback_function_files +
                      generated_core_callback_function_files
@@ -267,8 +281,10 @@ generated_core_testing_dictionary_files =
 # Compile the non-test sources generated above.
 blink_core_sources("bindings_core_impl") {
   _non_testing_sources = get_target_outputs(":bindings_core_impl_generated") -
-                         generated_core_testing_dictionary_files -
                          generated_core_testing_callback_function_files
+  if (!use_v8_bind_gen_for_dictionary) {
+    _non_testing_sources -= generated_core_testing_dictionary_files
+  }
   sources = _non_testing_sources + bindings_core_generated_interface_files +
             get_target_outputs(":bindings_core_origin_trial_features")
 

third_party/blink/renderer/bindings/modules/v8/BUILD.gn

@@ -2,6 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//third_party/blink/renderer/bindings/bindings.gni")
 import("//third_party/blink/renderer/bindings/modules/v8/generated.gni")
 import("//third_party/blink/renderer/bindings/scripts/scripts.gni")
 import("//third_party/blink/renderer/modules/modules.gni")
@@ -22,13 +23,20 @@ group("bindings_modules_v8_generated") {
 
 idl_compiler("generate_bindings_modules_v8_interfaces") {
   sources = modules_definition_idl_files
+  if (use_v8_bind_gen_for_dictionary) {
+    sources -= modules_dictionary_idl_files
+  }
   output_dir = bindings_modules_v8_output_dir
   output_name_suffix = ""
   target_component = "modules"
 }
 
 idl_impl("bindings_modules_impl_generated") {
-  dict_idls = modules_dictionary_idl_files
+  if (use_v8_bind_gen_for_dictionary) {
+    dict_idls = []
+  } else {
+    dict_idls = modules_dictionary_idl_files
+  }
   non_dict_outputs = bindings_modules_generated_union_type_files +
                      generated_modules_callback_function_files
   non_dict_output_dir = bindings_modules_v8_output_dir