[Bindings] Create and use V8 context snapshots

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

Index: third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp b/third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp
index 3b33bb890be160e9c7ee7d28faaae173b2a5a685..1faecaa91cd5714d845fa9920431ef05ec55807c 100644
--- a/third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp
@@ -39,6 +39,7 @@
 #include "bindings/core/v8/V8HTMLDocument.h"
 #include "bindings/core/v8/V8Initializer.h"
 #include "bindings/core/v8/V8PagePopupControllerBinding.h"
+#include "bindings/core/v8/V8SnapshotCreator.h"
 #include "bindings/core/v8/V8Window.h"
 #include "core/dom/Modulator.h"
 #include "core/frame/LocalFrame.h"
@@ -157,26 +158,27 @@ void LocalWindowProxy::Initialize() {
     SetSecurityToken(origin);
   }
 
-  MainThreadDebugger::Instance()->ContextCreated(script_state_.Get(),
-                                                 GetFrame(), origin);
-  GetFrame()->Loader().Client()->DidCreateScriptContext(context,
-                                                        world_->GetWorldId());
-  // If conditional features for window have been queued before the V8 context
-  // was ready, then inject them into the context now
-  if (world_->IsMainWorld()) {
-    InstallConditionalFeaturesOnWindow(script_state_.Get());
+  {
+    TRACE_EVENT1("v8", "notification", "isMainWindow",
+                 GetFrame()->IsMainFrame());
+    MainThreadDebugger::Instance()->ContextCreated(script_state_.Get(),
+                                                   GetFrame(), origin);
+    GetFrame()->Loader().Client()->DidCreateScriptContext(context,
+                                                          world_->GetWorldId());
+    // If conditional features for window have been queued before the V8 context
+    // was ready, then inject them into the context now
+    if (world_->IsMainWorld()) {
+      InstallConditionalFeaturesOnWindow(script_state_.Get());
+      GetFrame()->Loader().DispatchDidClearWindowObjectInMainWorld();
+    }
   }
-
-  if (world_->IsMainWorld())
-    GetFrame()->Loader().DispatchDidClearWindowObjectInMainWorld();
 }
 
 void LocalWindowProxy::CreateContext() {
-  // Create a new v8::Context with the window object as the global object
-  // (aka the inner global). Reuse the outer global proxy if it already exists.
-  v8::Local<v8::ObjectTemplate> global_template =
-      V8Window::domTemplate(GetIsolate(), *world_)->InstanceTemplate();
-  CHECK(!global_template.IsEmpty());
+  TRACE_EVENT1("v8", "LocalWindowProxy::CreateContext", "isMainWindow",
+               GetFrame()->IsMainFrame());
+
+  V8SnapshotCreator::EnsureInterfaceTemplates(GetIsolate(), World());
 
   Vector<const char*> extension_names;
   // Dynamically tell v8 about our extensions now.
@@ -193,9 +195,21 @@ void LocalWindowProxy::CreateContext() {
   {
     V8PerIsolateData::UseCounterDisabledScope use_counter_disabled(
         V8PerIsolateData::From(GetIsolate()));
-    context =
-        v8::Context::New(GetIsolate(), &extension_configuration,
-                         global_template, global_proxy_.NewLocal(GetIsolate()));
+    TRACE_EVENT1("v8", "contextCreation", "isMainWindow",
+                 GetFrame()->IsMainFrame());
+
+    v8::Local<v8::Object> global_proxy = global_proxy_.NewLocal(GetIsolate());
+    context = V8SnapshotCreator::CreateContext(
+        GetIsolate(), World(), &extension_configuration, global_proxy,
+        GetFrame()->GetDocument());
+
+    if (context.IsEmpty()) {
+      v8::Local<v8::ObjectTemplate> global_template =
+          V8Window::domTemplate(GetIsolate(), *world_)->InstanceTemplate();
+      CHECK(!global_template.IsEmpty());
+      context = v8::Context::New(GetIsolate(), &extension_configuration,
+                                 global_template, global_proxy);
+    }
   }
   CHECK(!context.IsEmpty());
 
@@ -212,6 +226,9 @@ void LocalWindowProxy::CreateContext() {
 }
 
 void LocalWindowProxy::SetupWindowPrototypeChain() {
+  TRACE_EVENT1("v8", "LocalWindowProxy::setupWindowPrototypeChain",
+               "isMainWindow", GetFrame()->IsMainFrame());
+
   // Associate the window wrapper object and its prototype chain with the
   // corresponding native DOMWindow object.
   DOMWindow* window = GetFrame()->DomWindow();
@@ -248,6 +265,9 @@ void LocalWindowProxy::SetupWindowPrototypeChain() {
   V8DOMWrapper::SetNativeInfo(GetIsolate(), window_properties,
                               wrapper_type_info, window);
 
+  V8SnapshotCreator::InstallRuntimeEnabledFeaturesOnGlobal(script_state_.Get(),
+                                                           window_wrapper);
+
   // TODO(keishi): Remove installPagePopupController and implement
   // PagePopupController in another way.
   V8PagePopupControllerBinding::InstallPagePopupController(context,
@@ -256,12 +276,18 @@ void LocalWindowProxy::SetupWindowPrototypeChain() {
 
 void LocalWindowProxy::UpdateDocumentProperty() {
   DCHECK(world_->IsMainWorld());
+  TRACE_EVENT1("v8", "LocalWindowProxy::updateDocumentProperty", "isMainWindow",
+               GetFrame()->IsMainFrame());
 
   ScriptState::Scope scope(script_state_.Get());
   v8::Local<v8::Context> context = script_state_->GetContext();
   v8::Local<v8::Value> document_wrapper =
       ToV8(GetFrame()->GetDocument(), context->Global(), GetIsolate());
   DCHECK(document_wrapper->IsObject());
+
+  V8SnapshotCreator::InstallRuntimeEnabledFeaturesOnDocument(
+      script_state_.Get(), document_wrapper.As<v8::Object>());

[haraken, 2017/05/20 19:10:02]

UpdateDocumentProperty() is called every time window.document gets updated. Is
it a right timing to install runtime-enabled features?

I guess we should install runtime-enabled features when the document wrapper is
instantiated.

[peria, 2017/05/30 08:25:44]

Agree. will do in the next update.

+
   // Update the cached accessor for window.document.
   CHECK(V8PrivateProperty::GetWindowDocumentCachedAccessor(GetIsolate())
             .Set(context->Global(), document_wrapper));
@@ -323,8 +349,8 @@ void LocalWindowProxy::SetSecurityToken(SecurityOrigin* origin) {
     String frame_security_token = frame_security_origin->ToString();
     // We need to check the return value of domainWasSetInDOM() on the
     // frame's SecurityOrigin because, if that's the case, only
-    // SecurityOrigin::m_domain would have been modified.
-    // m_domain is not used by SecurityOrigin::toString(), so we would end
+    // SecurityOrigin::domain_ would have been modified.
+    // domain_ is not used by SecurityOrigin::toString(), so we would end
     // up generating the same token that was already set.
     if (frame_security_origin->DomainWasSetInDOM() ||
         frame_security_token.IsEmpty() || frame_security_token == "null") {