Add code generation for ExperimentalFeatures class from RuntimeEnabledFeatures.

third_party/WebKit/Source/core/core_generated.gyp

Index: third_party/WebKit/Source/core/core_generated.gyp
diff --git a/third_party/WebKit/Source/core/core_generated.gyp b/third_party/WebKit/Source/core/core_generated.gyp
index ea2e60c5b8465668c85b993b1dfce6b158d33986..01712e3ba3aae41ea72718ab0be26a7ea6b41a1a 100644
--- a/third_party/WebKit/Source/core/core_generated.gyp
+++ b/third_party/WebKit/Source/core/core_generated.gyp
@@ -730,6 +730,27 @@
             '<(blink_core_output_dir)',
           ],
         },
+        {
+          'action_name': 'ExperimentalFeatures',
+          'inputs': [
+            '<@(scripts_for_in_files)',
+            '../build/scripts/make_experimental_features.py',
+            '../platform/RuntimeEnabledFeatures.in',
+            '../build/scripts/templates/ExperimentalFeatures.cpp.tmpl',
+            '../build/scripts/templates/ExperimentalFeatures.h.tmpl',
+          ],
+          'outputs': [
+            '<(blink_core_output_dir)/experiments/ExperimentalFeatures.cpp',
+            '<(blink_core_output_dir)/experiments/ExperimentalFeatures.h',
+          ],
+          'action': [
+            'python',
+            '../build/scripts/make_experimental_features.py',
+            '../platform/RuntimeEnabledFeatures.in',
+            '--output_dir',
+            '<(blink_core_output_dir)/experiments',
+          ],
+        },
       ],
       'rules': [
         {