Add code generation for ExperimentalFeatures class from RuntimeEnabledFeatures.

third_party/WebKit/Source/build/scripts/templates/ExperimentalFeatures.cpp.tmpl

Index: third_party/WebKit/Source/build/scripts/templates/ExperimentalFeatures.cpp.tmpl
diff --git a/third_party/WebKit/Source/build/scripts/templates/ExperimentalFeatures.cpp.tmpl b/third_party/WebKit/Source/build/scripts/templates/ExperimentalFeatures.cpp.tmpl
new file mode 100644
index 0000000000000000000000000000000000000000..d4edb9d1f3fb2f1cbfc3902998de45ca9d3a909c
--- /dev/null
+++ b/third_party/WebKit/Source/build/scripts/templates/ExperimentalFeatures.cpp.tmpl
@@ -0,0 +1,23 @@
+{% from 'macros.tmpl' import license %}
+{{license()}}
+
+#include "config.h"
+#include "core/experiments/ExperimentalFeatures.h"
+
+#include "core/experiments/Experiments.h"
+#include "platform/RuntimeEnabledFeatures.h"
+
+namespace blink {
+{% for feature in features %}
+{% if feature.api_name %}
+
+// static
+bool ExperimentalFeatures::{{feature.first_lowered_name}}Enabled(ExecutionContext* executionContext, String& errorMessage) {
+    if (RuntimeEnabledFeatures::{{feature.first_lowered_name}}Enabled())
+        return true;
+    return Experiments::isApiEnabled(executionContext, "{{feature.api_name}}", errorMessage);
+}
+{% endif %}
+{% endfor %}
+
+} // namespace blink