Switch blink to use a gin-managed isolate.

Source/web/WebKit.cpp

Index: Source/web/WebKit.cpp
diff --git a/Source/web/WebKit.cpp b/Source/web/WebKit.cpp
index 370d6141528c28f16bf3a834d136dc11e9b2cf0f..9411f97e35f2895436dc35c9887cec99e90d655c 100644
--- a/Source/web/WebKit.cpp
+++ b/Source/web/WebKit.cpp
@@ -92,29 +92,13 @@ static ThreadState::Interruptor* s_isolateInterruptor = 0;
 // Doing so may cause hard to reproduce crashes.
 static bool s_webKitInitialized = false;
 
-static bool generateEntropy(unsigned char* buffer, size_t length)
-{
-    if (Platform::current()) {
-        Platform::current()->cryptographicallyRandomValues(buffer, length);
-        return true;
-    }
-    return false;
-}
-
 void initialize(Platform* platform)
 {
     initializeWithoutV8(platform);
 
-    v8::V8::InitializePlatform(gin::V8Platform::Get());
-    v8::Isolate* isolate = v8::Isolate::New();
-    isolate->Enter();
-    V8Initializer::initializeMainThreadIfNeeded(isolate);
-    v8::V8::SetEntropySource(&generateEntropy);
-    v8::V8::SetArrayBufferAllocator(v8ArrayBufferAllocator());
-    v8::V8::Initialize();
-    V8PerIsolateData::ensureInitialized(isolate);
+    V8Initializer::initializeMainThreadIfNeeded();
 
-    s_isolateInterruptor = new V8IsolateInterruptor(v8::Isolate::GetCurrent());
+    s_isolateInterruptor = new V8IsolateInterruptor(V8PerIsolateData::mainThreadIsolate());
     ThreadState::current()->addInterruptor(s_isolateInterruptor);
 
     // currentThread will always be non-null in production, but can be null in Chromium unit tests.
@@ -224,8 +208,6 @@ void shutdown()
 
     v8::Isolate* isolate = V8PerIsolateData::mainThreadIsolate();
     V8PerIsolateData::dispose(isolate);
-    isolate->Exit();
-    isolate->Dispose();
 
     shutdownWithoutV8();
 }