Revert refactoring of CSSProperty .in files

Source/core/BUILD.gn

Index: Source/core/BUILD.gn
diff --git a/Source/core/BUILD.gn b/Source/core/BUILD.gn
index 5e7960377f1514602be6bd450410943c6c138129..296ec37f93b9968594c194aa6081bb29c51e6912 100644
--- a/Source/core/BUILD.gn
+++ b/Source/core/BUILD.gn
@@ -414,9 +414,6 @@ source_set("core_generated") {
     # Generated from make_style_builder.py
     "$blink_core_output_dir/StyleBuilder.cpp",
     "$blink_core_output_dir/StyleBuilderFunctions.cpp",
-
-    # Generated from make_css_property_metadata.py
-    "$blink_core_output_dir/CSSPropertyMetadata.cpp",
   ]
 
   configs -= core_config_remove
@@ -592,8 +589,12 @@ group("make_core_generated") {
 }
 
 # "CSSPropertyNames" in make_core_generated from GYP.
-css_properties("make_core_generated_css_property_names") {
+process_in_files("make_core_generated_css_property_names") {
   script = "../build/scripts/make_css_property_names.py"
+  in_files = [
+    "css/CSSPropertyNames.in",
+    "css/SVGCSSPropertyNames.in",
+  ]
   outputs = [
     "$blink_core_output_dir/CSSPropertyNames.cpp",
     "$blink_core_output_dir/CSSPropertyNames.h",
@@ -643,17 +644,6 @@ css_properties("make_core_generated_style_builder") {
   ]
 }
 
-# "CSSPropertyMetadata" in make_core_generated from GYP.
-css_properties("make_core_generated_css_property_metadata") {
-  script = "../build/scripts/make_css_property_metadata.py"
-  other_inputs = [
-    "../build/scripts/templates/CSSPropertyMetadata.cpp.tmpl",
-  ]
-  outputs = [
-    "$blink_core_output_dir/CSSPropertyMetadata.cpp",
-  ]
-}
-
 # "CSSValueKeywords" in make_core_generated from GYP.
 process_in_files("make_core_generated_css_value_keywords") {
   script = "../build/scripts/make_css_value_keywords.py"