Extract param struct to separate header

This change extracts param data related struct only used in mojom cc files to another header file, params-data.h.
And only mojom cc files include params-data.h.
By extracting structs, this CL reduces total size of included files from compiles including mojom headers.

This CL reduces total size of generated header files when building chrome.
mojom-shared.h: 9576659 -> 6343886
mojom-shared-internal.h: 7552016 -> 3053172

And this helped to reduce compile time.
e.g. obj/content/browser/browser/navigation_url_loader_impl.o: 25.6s -> 22.7s in Z840 Linux

chrome build time on 24C/48T Z840 Linux reduced from 3478.5s to 3385.5s.

Bug: 922875
Change-Id: I0e233e6046f9b47d6386ea24ea911da638b6aa69
Reviewed-on: https://chromium-review.googlesource.com/c/1436286
Commit-Queue: Takuto Ikuta <tikuta@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#626302}

mojo/public/tools/bindings/BUILD.gn

@@ -17,6 +17,7 @@ action("precompile_templates") {
     "$mojom_generator_root/generators/cpp_templates/interface_request_validator_declaration.tmpl",
     "$mojom_generator_root/generators/cpp_templates/interface_response_validator_declaration.tmpl",
     "$mojom_generator_root/generators/cpp_templates/interface_stub_declaration.tmpl",
+    "$mojom_generator_root/generators/cpp_templates/module-params-data.h.tmpl",
     "$mojom_generator_root/generators/cpp_templates/module-shared-internal.h.tmpl",
     "$mojom_generator_root/generators/cpp_templates/module-shared-message-ids.h.tmpl",
     "$mojom_generator_root/generators/cpp_templates/module-shared.cc.tmpl",

mojo/public/tools/bindings/generators/cpp_templates/module-params-data.h.tmpl

+// Copyright 2019 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.
+
+{%- set header_guard = "%s_PARAMS_DATA_H_"|format(
+        module.path|upper|replace("/","_")|replace(".","_")|
+            replace("-", "_")) %}
+
+#ifndef {{header_guard}}
+#define {{header_guard}}
+
+#include "base/logging.h"
+#include "base/macros.h"
+#include "mojo/public/cpp/bindings/lib/bindings_internal.h"
+#include "mojo/public/cpp/bindings/lib/buffer.h"
+#include "mojo/public/cpp/bindings/lib/validation_context.h"
+
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-private-field"
+#elif defined(_MSC_VER)
+#pragma warning(push)
+#pragma warning(disable:4056)
+#pragma warning(disable:4065)
+#pragma warning(disable:4756)
+#endif
+
+{%- for namespace in namespaces_as_array %}
+namespace {{namespace}} {
+{%- endfor %}
+namespace internal {
+
+{#--- Interface parameter definitions #}
+{%- for interface in interfaces %}
+{%-   for method in interface.methods %}
+{%-     set struct = method.param_struct %}
+{%      include "struct_declaration.tmpl" %}
+{%-     if method.response_parameters != None %}
+{%-       set struct = method.response_param_struct %}
+{%        include "struct_declaration.tmpl" %}
+{%-     endif %}
+{%-   endfor %}
+{%- endfor %}
+
+}  // namespace internal
+
+{#--- Interface parameter definitions #}
+{%- for interface in interfaces %}
+{%-   for method in interface.methods %}
+{%-     set struct = method.param_struct %}
+{%      include "struct_data_view_declaration.tmpl" %}
+{%-     if method.response_parameters != None %}
+{%-       set struct = method.response_param_struct %}
+{%        include "struct_data_view_declaration.tmpl" %}
+{%-     endif %}
+{%-   endfor %}
+{%- endfor %}
+
+{%- for interface in interfaces %}
+{%-   for method in interface.methods %}
+{%-     set struct = method.param_struct %}
+{%      include "struct_data_view_definition.tmpl" %}
+{%-     if method.response_parameters != None %}
+{%-       set struct = method.response_param_struct %}
+{%        include "struct_data_view_definition.tmpl" %}
+{%-     endif %}
+{%-   endfor %}
+{%- endfor %}
+
+{%- for namespace in namespaces_as_array|reverse %}
+}  // namespace {{namespace}}
+{%- endfor %}
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#elif defined(_MSC_VER)
+#pragma warning(pop)
+#endif
+
+#endif  // {{header_guard}}

mojo/public/tools/bindings/generators/cpp_templates/module-shared-internal.h.tmpl

@@ -78,18 +78,6 @@ using {{enum|get_name_for_kind(flatten_nested_kind=True)}}_Data =
 {%-   endif %}
 {%- endfor %}
 
-{#--- Interface parameter definitions #}
-{%- for interface in interfaces %}
-{%-   for method in interface.methods %}
-{%-     set struct = method.param_struct %}
-{%      include "struct_declaration.tmpl" %}
-{%-     if method.response_parameters != None %}
-{%-       set struct = method.response_param_struct %}
-{%        include "struct_declaration.tmpl" %}
-{%-     endif %}
-{%-   endfor %}
-{%- endfor %}
-
 #pragma pack(pop)
 
 }  // namespace internal

mojo/public/tools/bindings/generators/cpp_templates/module-shared.cc.tmpl

@@ -18,6 +18,8 @@
 #include "mojo/public/cpp/bindings/lib/validation_errors.h"
 #include "mojo/public/cpp/bindings/lib/validation_util.h"
 
+#include "{{module.path}}-params-data.h"
+
 {%- for header in extra_traits_headers %}
 #include "{{header}}"
 {%- endfor %}

mojo/public/tools/bindings/generators/cpp_templates/module-shared.h.tmpl

@@ -140,18 +140,6 @@ using {{interface.name}}AssociatedRequestDataView =
 {%-   endif %}
 {%- endfor %}
 
-{#--- Interface parameter definitions #}
-{%- for interface in interfaces %}
-{%-   for method in interface.methods %}
-{%-     set struct = method.param_struct %}
-{%      include "struct_data_view_declaration.tmpl" %}
-{%-     if method.response_parameters != None %}
-{%-       set struct = method.response_param_struct %}
-{%        include "struct_data_view_declaration.tmpl" %}
-{%-     endif %}
-{%-   endfor %}
-{%- endfor %}
-
 {#--- Unions #}
 {%- for union in unions %}
 {%    include "union_data_view_declaration.tmpl" %}
@@ -203,17 +191,6 @@ namespace mojo {
 {%-   endif %}
 {%- endfor %}
 
-{%- for interface in interfaces %}
-{%-   for method in interface.methods %}
-{%-     set struct = method.param_struct %}
-{%      include "struct_data_view_definition.tmpl" %}
-{%-     if method.response_parameters != None %}
-{%-       set struct = method.response_param_struct %}
-{%        include "struct_data_view_definition.tmpl" %}
-{%-     endif %}
-{%-   endfor %}
-{%- endfor %}
-
 {%- for union in unions %}
 {%    include "union_data_view_definition.tmpl" %}
 {%- endfor %}

mojo/public/tools/bindings/generators/cpp_templates/module.cc.tmpl

@@ -38,6 +38,7 @@
 #include "mojo/public/cpp/bindings/lib/validation_errors.h"
 #include "mojo/public/interfaces/bindings/interface_control_messages.mojom.h"
 
+#include "{{module.path}}-params-data.h"
 #include "{{module.path}}-shared-message-ids.h"
 
 {%- if for_blink %}

mojo/public/tools/bindings/generators/mojom_cpp_generator.py

@@ -404,6 +404,10 @@ class Generator(generator.Generator):
   def _GenerateModuleTestUtilsSource(self):
     return self._GetJinjaExports()
 
+  @UseJinja("module-params-data.h.tmpl")
+  def _GenerateModuleParamsDataHeader(self):
+    return self._GetJinjaExports()
+
   def GenerateFiles(self, args):
     self.module.Stylize(generator.Stylizer())
 
@@ -418,6 +422,8 @@ class Generator(generator.Generator):
                    "%s-shared-internal.h" % self.module.path)
         self.Write(self._GenerateModuleSharedSource(),
                    "%s-shared.cc" % self.module.path)
+        self.Write(self._GenerateModuleParamsDataHeader(),
+                   "%s-params-data.h" % self.module.path)
     else:
       suffix = "-%s" % self.variant if self.variant else ""
       self.Write(self._GenerateModuleHeader(),

mojo/public/tools/bindings/mojom.gni

@@ -617,6 +617,7 @@ template("mojom") {
     }
 
     generator_shared_cpp_outputs = [
+      "{{source_gen_dir}}/{{source_file_part}}-params-data.h",
       "{{source_gen_dir}}/{{source_file_part}}-shared-internal.h",
       "{{source_gen_dir}}/{{source_file_part}}-shared.cc",
       "{{source_gen_dir}}/{{source_file_part}}-shared.h",
@@ -638,6 +639,7 @@ template("mojom") {
       foreach(source, invoker.sources) {
         filelist += [ rebase_path("$source", root_build_dir) ]
         outputs += [
+          "$target_gen_dir/$source-params-data.h",
           "$target_gen_dir/$source-shared-internal.h",
           "$target_gen_dir/$source-shared.cc",
           "$target_gen_dir/$source-shared.h",