Refactor SkyShell to allow multiple SkyViews

sky/shell/android/platform_view_android.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sky/shell/android/platform_view_android.h"
 
 #include <android/input.h>
 #include <android/native_window_jni.h>
 
 #include "base/android/jni_android.h"
 #include "base/bind.h"
 #include "base/location.h"
 #include "jni/PlatformViewAndroid_jni.h"
+#include "sky/shell/instance.h"
 #include "sky/shell/shell.h"
 
 namespace sky {
 namespace shell {
 
 static jlong Attach(JNIEnv* env, jclass clazz, jint viewportObserverHandle) {
-  PlatformView* view = Shell::Shared().view();
+  Instance* instance = new Instance(Shell::Shared());
+  auto view = static_cast<PlatformViewAndroid*>(instance->view());
+  view->SetInstance(make_scoped_ptr(instance));
   view->ConnectToViewportObserver(
       mojo::MakeRequest<ViewportObserver>(mojo::ScopedMessagePipeHandle(
           mojo::MessagePipeHandle(viewportObserverHandle))));
-  return reinterpret_cast<jlong>(view);
+  return reinterpret_cast<jlong>(instance->view());
 }
 
 // static
 bool PlatformViewAndroid::Register(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
+PlatformView* PlatformView::Create(const Config& config) {
+  return new PlatformViewAndroid(config);
+}
+
+PlatformViewAndroid::PlatformViewAndroid(const Config& config)
+  : PlatformView(config) {
+}
+
 PlatformViewAndroid::~PlatformViewAndroid() {
   if (window_)
     ReleaseWindow();
 }
 
 void PlatformViewAndroid::Detach(JNIEnv* env, jobject obj) {
   DCHECK(!window_);
+  instance_.reset();
+  // Note: |this| has been destroyed at this point.
 }
 
 void PlatformViewAndroid::SurfaceCreated(JNIEnv* env, jobject obj, jobject jsurface) {
   base::android::ScopedJavaLocalRef<jobject> protector(env, jsurface);
   // Note: This ensures that any local references used by
   // ANativeWindow_fromSurface are released immediately. This is needed as a
   // workaround for https://code.google.com/p/android/issues/detail?id=68174
   {
     base::android::ScopedJavaLocalFrame scoped_local_reference_frame(env);
     window_ = ANativeWindow_fromSurface(env, jsurface);
   }
   SurfaceWasCreated();
 }
 
 void PlatformViewAndroid::SurfaceDestroyed(JNIEnv* env, jobject obj) {
   DCHECK(window_);
   SurfaceWasDestroyed();
   ReleaseWindow();
 }
 
+void PlatformViewAndroid::SetInstance(scoped_ptr<Instance> instance) {
+  DCHECK(!instance_);
+  instance_ = instance.Pass();
+}
+
 void PlatformViewAndroid::ReleaseWindow() {
   ANativeWindow_release(window_);
   window_ = nullptr;
 }
 
 }  // namespace shell
 }  // namespace sky