[bindings] Implement an ExperimentEnabled IDL extended attribute.

third_party/WebKit/Source/bindings/templates/methods.cpp

Index: third_party/WebKit/Source/bindings/templates/methods.cpp
diff --git a/third_party/WebKit/Source/bindings/templates/methods.cpp b/third_party/WebKit/Source/bindings/templates/methods.cpp
index c9295cdb161dd59f47fef4cb27ac0742c9f17d09..bc199592f896505a08ef0105b262e42a3691724b 100644
--- a/third_party/WebKit/Source/bindings/templates/methods.cpp
+++ b/third_party/WebKit/Source/bindings/templates/methods.cpp
@@ -366,7 +366,7 @@ createMinimumArityTypeErrorForMethod(info.GetIsolate(), "{{method.name}}", "{{in
 static int {{overloads.name}}MethodLength()
 {
     {% for length, runtime_enabled_functions in overloads.runtime_determined_lengths %}
-    {% for runtime_enabled_function in runtime_enabled_functions %}
+{% for runtime_enabled_function in runtime_enabled_functions %}
     {% filter runtime_enabled(runtime_enabled_function) %}
     return {{length}};
     {% endfilter %}
@@ -701,12 +701,10 @@ v8::Local<v8::Signature> defaultSignature = v8::Signature::New(isolate, domTempl
 ExecutionContext* executionContext = toExecutionContext(prototypeObject->CreationContext());
 ASSERT(executionContext);
 {% for method in conditionally_enabled_methods %}
-{% filter exposed(method.overloads.exposed_test_all
-                  if method.overloads else
-                  method.exposed_test) %}
-{% filter runtime_enabled(method.overloads.runtime_enabled_function_all
-                          if method.overloads else
-                          method.runtime_enabled_function) %}
+{% set runtime_enabled_function, api_experiment_name, exposure = (method.overloads.runtime_enabled_function_all, method.overloads.api_experiment_name_all, method.overloads.exposed_test_all) if method.overloads
+                              else (method.runtime_enabled_function, method.api_experiment_name, method.exposed_test) %}
+{% filter exposed(exposure) %}
+{% filter runtime_enabled(runtime_enabled_function) %}
 const V8DOMConfiguration::MethodConfiguration {{method.name}}MethodConfiguration = {{method_configuration(method)}};
 V8DOMConfiguration::installMethod(isolate, v8::Local<v8::Object>(), prototypeObject, interfaceObject, defaultSignature, {{method.name}}MethodConfiguration);
 {% endfilter %}{# runtime_enabled() #}