[Bindings] Create and use V8 context snapshots

third_party/WebKit/Source/bindings/core/v8/V8DOMConfiguration.cpp

Index: third_party/WebKit/Source/bindings/core/v8/V8DOMConfiguration.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/V8DOMConfiguration.cpp b/third_party/WebKit/Source/bindings/core/v8/V8DOMConfiguration.cpp
index 0ac2cb919c8facb5746e548989a81f6ae4158897..8d468ff91cea4fe67961b097447c4290821df151 100644
--- a/third_party/WebKit/Source/bindings/core/v8/V8DOMConfiguration.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/V8DOMConfiguration.cpp
@@ -107,12 +107,12 @@ void InstallAttributeInternal(
 
   DCHECK(location);
   v8::Local<v8::Context> context = isolate->GetCurrentContext();
-  if (location & V8DOMConfiguration::kOnInstance) {
+  if (location & V8DOMConfiguration::kOnInstance && !instance.IsEmpty()) {
     instance
         ->SetNativeDataProperty(context, name, getter, setter, data, attribute)
         .ToChecked();
   }
-  if (location & V8DOMConfiguration::kOnPrototype) {
+  if (location & V8DOMConfiguration::kOnPrototype && !prototype.IsEmpty()) {
     prototype
         ->SetNativeDataProperty(context, name, getter, setter, data, attribute)
         .ToChecked();
@@ -241,8 +241,9 @@ void InstallAccessorInternal(
   v8::Local<v8::Value> data =
       v8::External::New(isolate, const_cast<WrapperTypeInfo*>(accessor.data));
 
-  DCHECK(accessor.property_location_configuration);
-  if (accessor.property_location_configuration &
+  const unsigned location = accessor.property_location_configuration;
+  DCHECK(location);
+  if (location &
       (V8DOMConfiguration::kOnInstance | V8DOMConfiguration::kOnPrototype)) {
     v8::Local<FunctionOrTemplate> getter =
         CreateAccessorFunctionOrTemplate<FunctionOrTemplate>(
@@ -250,21 +251,21 @@ void InstallAccessorInternal(
     v8::Local<FunctionOrTemplate> setter =
         CreateAccessorFunctionOrTemplate<FunctionOrTemplate>(
             isolate, setter_callback, nullptr, data, signature, 1);
-    if (accessor.property_location_configuration &
-        V8DOMConfiguration::kOnInstance) {
+    if (location & V8DOMConfiguration::kOnInstance &&
+        !instance_or_template.IsEmpty()) {
       instance_or_template->SetAccessorProperty(
           name, getter, setter,
           static_cast<v8::PropertyAttribute>(accessor.attribute));
     }
-    if (accessor.property_location_configuration &
-        V8DOMConfiguration::kOnPrototype) {
+    if (location & V8DOMConfiguration::kOnPrototype &&
+        !prototype_or_template.IsEmpty()) {
       prototype_or_template->SetAccessorProperty(
           name, getter, setter,
           static_cast<v8::PropertyAttribute>(accessor.attribute));
     }
   }
-  if (accessor.property_location_configuration &
-      V8DOMConfiguration::kOnInterface) {
+  if (location & V8DOMConfiguration::kOnInterface &&
+      !interface_or_template.IsEmpty()) {
     // Attributes installed on the interface object must be static
     // attributes, so no need to specify a signature, i.e. no need to do
     // type check against a holder.
@@ -437,8 +438,9 @@ void InstallMethodInternal(
       V8DOMConfiguration::kDoNotCheckHolder)
     signature = v8::Local<v8::Signature>();
 
-  DCHECK(method.property_location_configuration);
-  if (method.property_location_configuration &
+  const unsigned location = method.property_location_configuration;
+  DCHECK(location);
+  if (location &
       (V8DOMConfiguration::kOnInstance | V8DOMConfiguration::kOnPrototype)) {
     v8::Local<v8::FunctionTemplate> function_template =
         v8::FunctionTemplate::New(isolate, callback, v8::Local<v8::Value>(),
@@ -449,23 +451,22 @@ void InstallMethodInternal(
     v8::Local<v8::Function> function =
         function_template->GetFunction(isolate->GetCurrentContext())
             .ToLocalChecked();
-    if (method.property_location_configuration &
-        V8DOMConfiguration::kOnInstance)
+    if (location & V8DOMConfiguration::kOnInstance && !instance.IsEmpty()) {
       instance
           ->DefineOwnProperty(
               isolate->GetCurrentContext(), name, function,
               static_cast<v8::PropertyAttribute>(method.attribute))
           .ToChecked();
-    if (method.property_location_configuration &
-        V8DOMConfiguration::kOnPrototype)
+    }
+    if (location & V8DOMConfiguration::kOnPrototype && !prototype.IsEmpty()) {
       prototype
           ->DefineOwnProperty(
               isolate->GetCurrentContext(), name, function,
               static_cast<v8::PropertyAttribute>(method.attribute))
           .ToChecked();
+    }
   }
-  if (method.property_location_configuration &
-      V8DOMConfiguration::kOnInterface) {
+  if (location & V8DOMConfiguration::kOnInterface && !interface.IsEmpty()) {
     // Operations installed on the interface object must be static
     // operations, so no need to specify a signature, i.e. no need to do
     // type check against a holder.
@@ -730,16 +731,16 @@ v8::Local<v8::FunctionTemplate> V8DOMConfiguration::DomClassTemplate(
     WrapperTypeInfo* wrapper_type_info,
     InstallTemplateFunction configure_dom_class_template) {
   V8PerIsolateData* data = V8PerIsolateData::From(isolate);
-  v8::Local<v8::FunctionTemplate> result =
+  v8::Local<v8::FunctionTemplate> interface_template =
       data->FindInterfaceTemplate(world, wrapper_type_info);
-  if (!result.IsEmpty())
-    return result;
+  if (!interface_template.IsEmpty())
+    return interface_template;
 
-  result = v8::FunctionTemplate::New(
+  interface_template = v8::FunctionTemplate::New(
       isolate, V8ObjectConstructor::IsValidConstructorMode);
-  configure_dom_class_template(isolate, world, result);
-  data->SetInterfaceTemplate(world, wrapper_type_info, result);
-  return result;
+  configure_dom_class_template(isolate, world, interface_template);
+  data->SetInterfaceTemplate(world, wrapper_type_info, interface_template);
+  return interface_template;
 }
 
 void V8DOMConfiguration::SetClassString(