Allow origin trials to be enabled by script

third_party/WebKit/Source/bindings/modules/v8/ConditionalFeaturesForModules.cpp

Index: third_party/WebKit/Source/bindings/modules/v8/ConditionalFeaturesForModules.cpp
diff --git a/third_party/WebKit/Source/bindings/modules/v8/ConditionalFeaturesForModules.cpp b/third_party/WebKit/Source/bindings/modules/v8/ConditionalFeaturesForModules.cpp
index 05b68ce4422fe2f66c5c1a236da3e879aa34f7ce..7454945574931e3017fc978d8a1e6a0b13585bbc 100644
--- a/third_party/WebKit/Source/bindings/modules/v8/ConditionalFeaturesForModules.cpp
+++ b/third_party/WebKit/Source/bindings/modules/v8/ConditionalFeaturesForModules.cpp
@@ -29,6 +29,10 @@ namespace blink {
 namespace {
 InstallConditionalFeaturesFunction
     s_originalInstallConditionalFeaturesFunction = nullptr;
+InstallConditionalFeaturesIfNeededFunction
+    s_originalInstallConditionalFeaturesIfNeededFunction = nullptr;
+GetAffectedTypesForConditionalFeatureFunction
+    s_originalGetAffectedTypesForConditionalFeatureFunction = nullptr;
 }
 
 void installConditionalFeaturesForModules(
@@ -140,10 +144,61 @@ void installConditionalFeaturesForModules(
   }
 }
 
+bool installConditionalFeaturesIfNeededForModules(
+    const WrapperTypeInfo* wrapperTypeInfo,
+    const ScriptState* scriptState) {
+  (*s_originalInstallConditionalFeaturesIfNeededFunction)(wrapperTypeInfo,
+                                                          scriptState);
+
+  // Only install features here, if the target type has an existing instance

[iclelland, 2017/01/20 14:31:19]

I think rather than instance, you mean prototype/constructor here.

[chasej, 2017/01/25 19:58:20]

This method is gone in the new, simplified approach.

+  V8PerContextData* contextData = scriptState->perContextData();
+  if (wrapperTypeInfo == &V8Navigator::wrapperTypeInfo) {
+    v8::Local<v8::Function> interfaceObject =
+        contextData->constructorForTypeFromCache(wrapperTypeInfo);
+    if (interfaceObject.IsEmpty()) {
+      LOG(INFO) << "No existing instance for type: "
+                << wrapperTypeInfo->interfaceName;
+      return true;
+    }
+    LOG(INFO) << "Found existing instance for type: "
+              << wrapperTypeInfo->interfaceName;
+    v8::Local<v8::Object> prototypeObject =
+        contextData->prototypeForType(wrapperTypeInfo);
+
+    installConditionalFeaturesForModules(wrapperTypeInfo, scriptState,
+                                         prototypeObject, interfaceObject);
+    return true;
+  }
+  return false;
+}
+
+void getAffectedTypesForConditionalFeatureFunctionForModules(
+    const String& feature,
+    HashSet<const WrapperTypeInfo*>* affectedTypes) {
+  (*s_originalGetAffectedTypesForConditionalFeatureFunction)(feature,
+                                                             affectedTypes);
+  if (feature == "ServiceWorkerNavigationPreload") {

[iclelland, 2017/01/20 14:31:19]

Is this method eventually intended to cover all of the trial features which are
handled in installConditionalFeaturesForModules, or is this going to be a
hand-curated list?

[chasej, 2017/01/25 19:58:20]

This method is gone in the new, simplified approach.

+    // affectedTypes->add(&V8Navigator::wrapperTypeInfo);
+    affectedTypes->add(&V8Window::wrapperTypeInfo);
+    return;
+  }
+  if (feature == "WebUSB") {
+    affectedTypes->add(&V8Navigator::wrapperTypeInfo);
+    affectedTypes->add(&V8Window::wrapperTypeInfo);
+    return;
+  }
+}
+
 void registerInstallConditionalFeaturesForModules() {
   s_originalInstallConditionalFeaturesFunction =
       setInstallConditionalFeaturesFunction(
           &installConditionalFeaturesForModules);
+  s_originalInstallConditionalFeaturesIfNeededFunction =
+      setInstallConditionalFeaturesIfNeededFunction(
+          &installConditionalFeaturesIfNeededForModules);
+  s_originalGetAffectedTypesForConditionalFeatureFunction =
+      setGetAffectedTypesForConditionalFeatureFunction(
+          &getAffectedTypesForConditionalFeatureFunctionForModules);
 }
 
 }  // namespace blink