Added dependency to jinja2 sources for mojom generator

mojom generator uses jinja2 template.
If we update jinja2 library, jinja2 may update api/internal structure.
In such case, all mojom generator using jinja2 may need to re-run.

I added jinja2_sources for such case and use it as inputs dependency for mojom generator action.
It is recommended by gn.
https://chromium.googlesource.com/chromium/src/+/master/tools/gn/docs/reference.md#target-declarations-action_declare-a-target-that-runs-a-script-a-single-time-inputs

* Minor fix
Update README.chromium to pass current presubmit check.

Change-Id: I8b7f126c3a807ac211db01c90437d584c9c39f85
Reviewed-on: https://chromium-review.googlesource.com/961763Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Yuki Shiino <yukishiino@chromium.org>
Reviewed-by: Ken Rockot <rockot@chromium.org>
Commit-Queue: Takuto Ikuta <tikuta@google.com>
Cr-Commit-Position: refs/heads/master@{#543073}

mojo/public/tools/bindings/BUILD.gn

@@ -3,6 +3,7 @@
 # found in the LICENSE file.
 
 import("//mojo/public/tools/bindings/mojom.gni")
+import("//third_party/jinja2/jinja2.gni")
 
 action("precompile_templates") {
   sources = mojom_generator_sources
@@ -68,6 +69,8 @@ action("precompile_templates") {
     "$mojom_generator_root/generators/js_templates/validation_macros.tmpl",
   ]
   script = mojom_generator_script
+
+  inputs = jinja2_sources
   outputs = [
     "$target_gen_dir/cpp_templates.zip",
     "$target_gen_dir/java_templates.zip",

mojo/public/tools/bindings/mojom.gni

@@ -12,6 +12,7 @@ import("//build/config/jumbo.gni")
 import("//build/config/chrome_build.gni")
 import("//build/config/nacl/config.gni")
 import("//components/nacl/features.gni")
+import("//third_party/jinja2/jinja2.gni")
 
 declare_args() {
   # Indicates whether typemapping should be supported in this build
@@ -399,7 +400,7 @@ template("mojom") {
     }
     action_foreach(parser_target_name) {
       script = mojom_generator_script
-      inputs = mojom_generator_sources
+      inputs = mojom_generator_sources + jinja2_sources
       sources = invoker.sources
       outputs = [
         "{{source_gen_dir}}/{{source_name_part}}.p",
@@ -444,7 +445,7 @@ template("mojom") {
       source_file_name = target_name
       action_foreach(verify_deps_target_name) {
         script = mojom_generator_script
-        inputs = mojom_generator_sources
+        inputs = mojom_generator_sources + jinja2_sources
         sources = invoker.sources
         deps = [
           ":$parsed_target_name",
@@ -537,7 +538,7 @@ template("mojom") {
 
     action_foreach(generator_cpp_message_ids_target_name) {
       script = mojom_generator_script
-      inputs = mojom_generator_sources
+      inputs = mojom_generator_sources + jinja2_sources
       sources = invoker.sources
       deps = [
         ":$parsed_target_name",
@@ -569,7 +570,7 @@ template("mojom") {
     generator_shared_target_name = "${target_name}_shared__generator"
     action_foreach(generator_shared_target_name) {
       script = mojom_generator_script
-      inputs = mojom_generator_sources
+      inputs = mojom_generator_sources + jinja2_sources
       sources = invoker.sources
       deps = [
                ":$parsed_target_name",
@@ -743,7 +744,7 @@ template("mojom") {
       generator_target_name = "${target_name}${variant_suffix}__generator"
       action_foreach(generator_target_name) {
         script = mojom_generator_script
-        inputs = mojom_generator_sources
+        inputs = mojom_generator_sources + jinja2_sources
         sources = invoker.sources
         deps = [
                  ":$parsed_target_name",
@@ -813,7 +814,8 @@ template("mojom") {
     }
 
     action(type_mappings_target_name) {
-      inputs = _bindings_configuration_files + mojom_generator_sources
+      inputs = _bindings_configuration_files + mojom_generator_sources +
+               jinja2_sources
       outputs = [
         type_mappings_path,
       ]
@@ -994,7 +996,7 @@ template("mojom") {
             [ "{{source_gen_dir}}/{{source_name_part}}.mojom.srcjar" ]
         action_foreach(java_generator_target_name) {
           script = mojom_generator_script
-          inputs = mojom_generator_sources
+          inputs = mojom_generator_sources + jinja2_sources
           sources = enabled_sources
           deps = [
                    ":$parsed_target_name",
@@ -1078,7 +1080,7 @@ template("mojom") {
       ]
       action_foreach(generator_js_target_name) {
         script = mojom_generator_script
-        inputs = mojom_generator_sources
+        inputs = mojom_generator_sources + jinja2_sources
         sources = []
         if (defined(invoker.sources)) {
           sources += invoker.sources

third_party/jinja2/README.chromium

@@ -2,8 +2,8 @@ Name: Jinja2 Python Template Engine
 Short Name: jinja2
 URL: http://jinja.pocoo.org/
 Version: 2.8
-License: BSD 3-clause License
-License File: NOT_SHIPPED
+License: BSD 3-Clause
+License File: LICENSE
 Security Critical: no
 
 Description:
@@ -19,7 +19,8 @@ AUTHORS files. Unit tests (testsuite directory) have been removed.
 Additional chromium-specific files are:
 * README.chromium (this file)
 * OWNERS
-* install script (get_jinja2.sh)
+* get_jinja2.sh (install script)
+* jinja2.gni (generated by get_jinja2.sh)
 * files of hashes (MD5 is also posted on website, SHA-512 computed locally).
 Script checks hash then unpacks archive and installs desired files.
 Retrieve or update by executing jinja2/get_jinja2.sh from third_party.

third_party/jinja2/get_jinja2.sh

@@ -120,3 +120,17 @@ mv "$INSTALL_DIR" "$OLD_DIR"
 mv "$PACKAGE_DIR" "$INSTALL_DIR"
 cd "$INSTALL_DIR"
 rm -fr "$OLD_DIR"
+
+# Generating jinja2.gni
+cat > jinja2.gni <<EOF
+# DO NOT EDIT
+# This is generated from get_jinja2.sh.
+jinja2_sources = [
+EOF
+
+for i in $(LC_COLLATE=C ls *.py)
+do
+  echo "  \"//third_party/jinja2/${i}\"," >> jinja2.gni
+done
+
+echo "]" >> jinja2.gni

third_party/jinja2/jinja2.gni

+# DO NOT EDIT
+# This is generated from get_jinja2.sh.
+jinja2_sources = [
+  "//third_party/jinja2/__init__.py",
+  "//third_party/jinja2/_compat.py",
+  "//third_party/jinja2/_stringdefs.py",
+  "//third_party/jinja2/bccache.py",
+  "//third_party/jinja2/compiler.py",
+  "//third_party/jinja2/constants.py",
+  "//third_party/jinja2/debug.py",
+  "//third_party/jinja2/defaults.py",
+  "//third_party/jinja2/environment.py",
+  "//third_party/jinja2/exceptions.py",
+  "//third_party/jinja2/ext.py",
+  "//third_party/jinja2/filters.py",
+  "//third_party/jinja2/lexer.py",
+  "//third_party/jinja2/loaders.py",
+  "//third_party/jinja2/meta.py",
+  "//third_party/jinja2/nodes.py",
+  "//third_party/jinja2/optimizer.py",
+  "//third_party/jinja2/parser.py",
+  "//third_party/jinja2/runtime.py",
+  "//third_party/jinja2/sandbox.py",
+  "//third_party/jinja2/tests.py",
+  "//third_party/jinja2/utils.py",
+  "//third_party/jinja2/visitor.py",
+]