Revert of [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 acb6b023af1f4c098fc1c4010a0f11e866f5cfd4..2b02bcf116801155f73c38f52b59a16f9ed96093 100644
--- a/third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp
@@ -33,7 +33,6 @@
 #include "bindings/core/v8/ScriptController.h"
 #include "bindings/core/v8/ToV8ForCore.h"
 #include "bindings/core/v8/V8BindingForCore.h"
-#include "bindings/core/v8/V8ContextSnapshot.h"
 #include "bindings/core/v8/V8DOMActivityLogger.h"
 #include "bindings/core/v8/V8GCForContextDispose.h"
 #include "bindings/core/v8/V8HTMLDocument.h"
@@ -115,7 +114,7 @@
 }
 
 void LocalWindowProxy::Initialize() {
-  TRACE_EVENT1("v8", "LocalWindowProxy::Initialize", "IsMainFrame",
+  TRACE_EVENT1("v8", "LocalWindowProxy::initialize", "isMainWindow",
                GetFrame()->IsMainFrame());
   SCOPED_BLINK_UMA_HISTOGRAM_TIMER(
       GetFrame()->IsMainFrame()
@@ -136,8 +135,6 @@
   }
 
   SetupWindowPrototypeChain();
-  V8ContextSnapshot::InstallRuntimeEnabledFeatures(context,
-                                                   GetFrame()->GetDocument());
 
   SecurityOrigin* origin = 0;
   if (world_->IsMainWorld()) {
@@ -158,32 +155,31 @@
     SetSecurityToken(origin);
   }
 
-  {
-    TRACE_EVENT1("v8", "ContextCreatedNotification", "IsMainFrame",
-                 GetFrame()->IsMainFrame());
-    MainThreadDebugger::Instance()->ContextCreated(script_state_.Get(),
-                                                   GetFrame(), origin);
-    GetFrame()->Client()->DidCreateScriptContext(context, world_->GetWorldId());
-
-    InstallConditionalFeaturesOnGlobal(&V8Window::wrapperTypeInfo,
-                                       script_state_.Get());
-
-    if (world_->IsMainWorld()) {
-      // For the main world, install any remaining conditional bindings (i.e.
-      // for origin trials, which do not apply to extensions). Some conditional
-      // bindings cannot be enabled until the execution context is available
-      // (e.g. parsing the document, inspecting HTTP headers).
-      InstallConditionalFeatures(&V8Window::wrapperTypeInfo,
-                                 script_state_.Get(), v8::Local<v8::Object>(),
-                                 v8::Local<v8::Function>());
-      GetFrame()->Loader().DispatchDidClearWindowObjectInMainWorld();
-    }
+  MainThreadDebugger::Instance()->ContextCreated(script_state_.Get(),
+                                                 GetFrame(), origin);
+  GetFrame()->Client()->DidCreateScriptContext(context, world_->GetWorldId());
+
+  InstallConditionalFeaturesOnGlobal(&V8Window::wrapperTypeInfo,
+                                     script_state_.Get());
+
+  if (world_->IsMainWorld()) {
+    // For the main world, install any remaining conditional bindings (i.e. for
+    // origin trials, which do not apply to extensions). Some conditional
+    // bindings cannot be enabled until the execution context is available
+    // (e.g. parsing the document, inspecting HTTP headers).
+    InstallConditionalFeatures(&V8Window::wrapperTypeInfo, script_state_.Get(),
+                               v8::Local<v8::Object>(),
+                               v8::Local<v8::Function>());
+    GetFrame()->Loader().DispatchDidClearWindowObjectInMainWorld();
   }
 }
 
 void LocalWindowProxy::CreateContext() {
-  TRACE_EVENT1("v8", "LocalWindowProxy::CreateContext", "IsMainFrame",
-               GetFrame()->IsMainFrame());
+  // 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());
 
   Vector<const char*> extension_names;
   // Dynamically tell v8 about our extensions now.
@@ -198,25 +194,11 @@
 
   v8::Local<v8::Context> context;
   {
-    v8::Isolate* isolate = GetIsolate();
-    Document* document = GetFrame()->GetDocument();
     V8PerIsolateData::UseCounterDisabledScope use_counter_disabled(
-        V8PerIsolateData::From(isolate));
-
-    v8::Local<v8::Object> global_proxy = global_proxy_.NewLocal(isolate);
-    context = V8ContextSnapshot::CreateContextFromSnapshot(
-        isolate, World(), &extension_configuration, global_proxy, document);
-
-    // Even if we enable V8 context snapshot feature, we may hit this branch
-    // in some cases, e.g. loading XML files.
-    if (context.IsEmpty()) {
-      v8::Local<v8::ObjectTemplate> global_template =
-          V8Window::domTemplate(isolate, *world_)->InstanceTemplate();
-      CHECK(!global_template.IsEmpty());
-      context = v8::Context::New(isolate, &extension_configuration,
-                                 global_template, global_proxy);
-      VLOG(1) << "A context is created NOT from snapshot";
-    }
+        V8PerIsolateData::From(GetIsolate()));
+    context =
+        v8::Context::New(GetIsolate(), &extension_configuration,
+                         global_template, global_proxy_.NewLocal(GetIsolate()));
   }
   CHECK(!context.IsEmpty());
 
@@ -233,9 +215,6 @@
 }
 
 void LocalWindowProxy::SetupWindowPrototypeChain() {
-  TRACE_EVENT1("v8", "LocalWindowProxy::SetupWindowPrototypeChain",
-               "IsMainFrame", GetFrame()->IsMainFrame());
-
   // Associate the window wrapper object and its prototype chain with the
   // corresponding native DOMWindow object.
   DOMWindow* window = GetFrame()->DomWindow();
@@ -280,15 +259,12 @@
 
 void LocalWindowProxy::UpdateDocumentProperty() {
   DCHECK(world_->IsMainWorld());
-  TRACE_EVENT1("v8", "LocalWindowProxy::UpdateDocumentProperty", "IsMainFrame",
-               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());
-
   // Update the cached accessor for window.document.
   CHECK(V8PrivateProperty::GetWindowDocumentCachedAccessor(GetIsolate())
             .Set(context->Global(), document_wrapper));
@@ -350,8 +326,8 @@
     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::domain_ would have been modified.
-    // domain_ is not used by SecurityOrigin::toString(), so we would end
+    // SecurityOrigin::m_domain would have been modified.
+    // m_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") {