Add a webview service for cast_shell

The client will use GRPC to talk to cast_shell to create and manage
webviews. One RPC corresponds to a given webview and input and
commands and send over this channel. Presentation is handled by
wayland/exo and associating a wayland surface with a webview

TEST=local test w/ desktop cast_shell & wayland_fullscreen_client
BUG=b/132811925

Change-Id: I8f0da747805973174c46f1d824758c6c2ee04674
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1678288
Commit-Queue: Albert Chaulk <achaulk@chromium.org>
Reviewed-by: Yuwei Huang <yuweih@chromium.org>
Reviewed-by: Joe Downing <joedow@chromium.org>
Reviewed-by: Daniele Castagna <dcastagna@chromium.org>
Reviewed-by: Daniel Nicoara <dnicoara@chromium.org>
Cr-Commit-Position: refs/heads/master@{#678456}

chromecast/browser/BUILD.gn

@@ -381,8 +381,16 @@ cast_source_set("browser") {
       "exo/wayland_server_controller.h",
       "exo/wm_helper_cast_shell.cc",
       "exo/wm_helper_cast_shell.h",
+      "webview/webview_controller.cc",
+      "webview/webview_controller.h",
+      "webview/webview_grpc_service.cc",
+      "webview/webview_grpc_service.h",
+      "webview/webview_layout_manager.cc",
+      "webview/webview_layout_manager.h",
     ]
+    configs += [ "//third_party/grpc:grpc_config" ]
     deps += [
+      "//chromecast/browser/webview/proto",
       "//components/exo",
       "//components/exo/wayland",
       "//services/viz/privileged/interfaces/compositing",

chromecast/browser/webview/DEPS

+include_rules = [
+  "+components/exo",
+  "+third_party/grpc",
+]

chromecast/browser/webview/proto/BUILD.gn

+# Copyright 2019 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.
+
+import("//third_party/grpc/grpc_library.gni")
+
+cc_grpc_library("proto") {
+  sources = [
+    "webview.proto",
+  ]
+}

chromecast/browser/webview/proto/webview.proto

+// Copyright 2019 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.
+
+// This provides an API to create and control webviews via gRPC.
+// Each webview is a separate bidirectional message stream, the client creates
+// a new one by sending a WebviewCreate message first. Subsequently, the client
+// navigates and injects input as desired and the server will respond with
+// event messages whenever page state changes, whether or not in direct response
+// to client actions, eg if the renderer crashes.
+
+syntax = "proto3";
+option optimize_for = LITE_RUNTIME;
+package chromecast.webview;
+
+message AccessibilityTreeInfo {
+  string ax_tree_id = 1;
+}
+
+// Create a new, empty webview
+message WebviewCreateRequest {
+  // This identifies the surface that this webview will display into.
+  // It should be unique and the same as whatever was set into
+  // |aura_surface_set_client_surface_id| on the wayland surface.
+  // It is an error to attempt to create a webview if the surface
+  // does not yet exist.
+  int32 webview_id = 1;
+  // This is the cast window ID that will be assigned to the web contents
+  // window.
+  int32 window_id = 2;
+}
+
+message WebviewCreateResponse {
+  AccessibilityTreeInfo accessibility_info = 1;
+}
+
+// These are a translation of ui::Event and children.
+message KeyInput {
+  int32 key_code = 1;
+  int32 dom_code = 2;
+  int32 dom_key = 3;
+  bool is_char = 4;
+}
+
+message TouchInput {
+  float x = 1;
+  float y = 2;
+  float root_x = 3;
+  float root_y = 4;
+  int32 pointer_type = 5;
+  int32 pointer_id = 6;
+  float radius_x = 7;
+  float radius_y = 8;
+  float force = 9;
+  float twist = 10;
+  float tilt_x = 11;
+  float tilt_y = 12;
+  float tangential_pressure = 13;
+}
+
+message MouseEvent {
+  float x = 1;
+  float y = 2;
+  float root_x = 3;
+  float root_y = 4;
+  int32 changed_button_flags = 5;
+}
+
+message InputEvent {
+  int32 event_type = 1;
+  int32 flags = 2;
+  int64 timestamp = 3;
+  KeyInput key = 4;
+  TouchInput touch = 5;
+  MouseEvent mouse = 6;
+}
+
+// Navigate this webview to the provided url.
+message NavigateRequest {
+  string url = 1;
+}
+
+message AsyncPageEvent {
+  enum State {
+    IDLE = 0;
+    LOADING = 1;
+    LOADED = 2;
+    CLOSED = 3;
+    DESTROYED = 4;
+    ERROR = 5;
+  }
+  // This is always set to the current state.
+  State current_page_state = 1;
+  // These will be set if the event just happened.
+  int32 stopped_error_code = 2;
+  bool resource_load_failed = 3;
+  bool did_first_visually_non_empty_paint = 4;
+}
+
+message StopPageRequest {
+  int32 error_code = 1;
+}
+
+message WebviewRequest {
+  oneof type {
+    // This must be the first message.
+    WebviewCreateRequest create = 1;
+    // No response.
+    InputEvent input = 2;
+    // Expect page events to follow.
+    NavigateRequest navigate = 3;
+    // Expect page events to follow.
+    StopPageRequest stop_page = 4;
+  }
+}
+
+message WebviewResponse {
+  oneof type {
+    WebviewCreateResponse create_response = 1;
+    AsyncPageEvent page_event = 2;
+  }
+}
+
+service WebviewService {
+  rpc CreateWebview(stream WebviewRequest) returns (stream WebviewResponse);
+}

chromecast/browser/webview/webview_controller.cc

+// Copyright 2019 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 "chromecast/browser/webview/webview_controller.h"
+
+#include "chromecast/base/version.h"
+#include "chromecast/browser/cast_web_contents_impl.h"
+#include "chromecast/browser/webview/proto/webview.pb.h"
+#include "chromecast/browser/webview/webview_layout_manager.h"
+#include "content/public/browser/web_contents.h"
+#include "ui/aura/window.h"
+#include "ui/aura/window_delegate.h"
+#include "ui/events/event.h"
+
+namespace chromecast {
+
+WebviewController::WebviewController(content::BrowserContext* browser_context,
+                                     Client* client)
+    : client_(client) {
+  content::WebContents::CreateParams create_params(browser_context, nullptr);
+  contents_ = content::WebContents::Create(create_params);
+  CastWebContents::InitParams cast_contents_init;
+  cast_contents_init.is_root_window = true;
+  cast_contents_init.enabled_for_dev = CAST_IS_DEBUG_BUILD();
+  cast_contents_init.delegate = this;
+  cast_web_contents_ = std::make_unique<CastWebContentsImpl>(
+      contents_.get(), cast_contents_init);
+
+  std::unique_ptr<webview::WebviewResponse> response =
+      std::make_unique<webview::WebviewResponse>();
+  auto ax_id = contents_->GetMainFrame()->GetAXTreeID().ToString();
+  response->mutable_create_response()
+      ->mutable_accessibility_info()
+      ->set_ax_tree_id(ax_id);
+  client->EnqueueSend(std::move(response));
+}
+
+WebviewController::~WebviewController() {}
+
+void WebviewController::ProcessRequest(const webview::WebviewRequest& request) {
+  switch (request.type_case()) {
+    case webview::WebviewRequest::kInput:
+      ProcessInputEvent(request.input());
+      break;
+
+    case webview::WebviewRequest::kNavigate:
+      if (request.has_navigate()) {
+        LOG(INFO) << "Navigate webview to " << request.navigate().url();
+        stopped_ = false;
+        cast_web_contents_->LoadUrl(GURL(request.navigate().url()));
+      } else {
+        client_->OnError("navigate() not supplied");
+      }
+      break;
+
+    case webview::WebviewRequest::kStopPage:
+      if (request.has_stop_page()) {
+        cast_web_contents_->Stop(request.stop_page().error_code());
+      } else {
+        client_->OnError("stop_page() not supplied");
+      }
+      break;
+
+    default:
+      client_->OnError("Unknown request code");
+      break;
+  }
+}
+
+void WebviewController::ClosePage() {
+  cast_web_contents_->ClosePage();
+}
+
+void WebviewController::AttachTo(aura::Window* window, int window_id) {
+  auto* contents_window = contents_->GetNativeView();
+  window->SetLayoutManager(new WebviewLayoutManager(contents_window));
+  contents_window->set_id(window_id);
+  contents_window->SetBounds(gfx::Rect(window->bounds().size()));
+  contents_window->Show();
+  window->AddChild(contents_->GetNativeView());
+}
+
+void WebviewController::ProcessInputEvent(const webview::InputEvent& ev) {
+  ui::EventHandler* handler = contents_->GetNativeView()->delegate();
+  ui::EventType type = static_cast<ui::EventType>(ev.event_type());
+  switch (type) {
+    case ui::ET_TOUCH_RELEASED:
+    case ui::ET_TOUCH_PRESSED:
+    case ui::ET_TOUCH_MOVED:
+    case ui::ET_TOUCH_CANCELLED:
+      if (ev.has_touch()) {
+        auto& touch = ev.touch();
+        ui::TouchEvent evt(
+            type, gfx::PointF(touch.x(), touch.y()),
+            gfx::PointF(touch.root_x(), touch.root_y()),
+            base::TimeTicks() +
+                base::TimeDelta::FromMicroseconds(ev.timestamp()),
+            ui::PointerDetails(
+                static_cast<ui::EventPointerType>(touch.pointer_type()),
+                static_cast<ui::PointerId>(touch.pointer_id()),
+                touch.radius_x(), touch.radius_y(), touch.force(),
+                touch.twist(), touch.tilt_x(), touch.tilt_y(),
+                touch.tangential_pressure()),
+            ev.flags());
+        handler->OnTouchEvent(&evt);
+      } else {
+        client_->OnError("touch() not supplied for touch event");
+      }
+      break;
+    case ui::ET_MOUSE_PRESSED:
+    case ui::ET_MOUSE_DRAGGED:
+    case ui::ET_MOUSE_RELEASED:
+    case ui::ET_MOUSE_MOVED:
+    case ui::ET_MOUSE_ENTERED:
+    case ui::ET_MOUSE_EXITED:
+    case ui::ET_MOUSEWHEEL:
+    case ui::ET_MOUSE_CAPTURE_CHANGED:
+      if (ev.has_mouse()) {
+        auto& mouse = ev.mouse();
+        ui::MouseEvent evt(
+            type, gfx::PointF(mouse.x(), mouse.y()),
+            gfx::PointF(mouse.root_x(), mouse.root_y()),
+            base::TimeTicks() +
+                base::TimeDelta::FromMicroseconds(ev.timestamp()),
+            ev.flags(), mouse.changed_button_flags());
+        handler->OnMouseEvent(&evt);
+      } else {
+        client_->OnError("mouse() not supplied for mouse event");
+      }
+      break;
+    default:
+      break;
+  }
+}
+
+webview::AsyncPageEvent_State WebviewController::current_state() {
+  // The PB enum is defined identically.
+  return static_cast<webview::AsyncPageEvent_State>(
+      cast_web_contents_->page_state());
+}
+
+void WebviewController::OnPageStateChanged(CastWebContents* cast_web_contents) {
+  if (client_) {
+    std::unique_ptr<webview::WebviewResponse> response =
+        std::make_unique<webview::WebviewResponse>();
+    auto* event = response->mutable_page_event();
+    event->set_current_page_state(current_state());
+    client_->EnqueueSend(std::move(response));
+  }
+}
+
+void WebviewController::OnPageStopped(CastWebContents* cast_web_contents,
+                                      int error_code) {
+  stopped_ = true;
+  if (client_) {
+    std::unique_ptr<webview::WebviewResponse> response =
+        std::make_unique<webview::WebviewResponse>();
+    auto* event = response->mutable_page_event();
+    event->set_current_page_state(current_state());
+    event->set_stopped_error_code(error_code);
+    client_->EnqueueSend(std::move(response));
+  } else {
+    // Can't destroy in an observer callback, so post a task to do it.
+    base::ThreadTaskRunnerHandle::Get()->DeleteSoon(FROM_HERE, this);
+  }
+}
+
+void WebviewController::ResourceLoadFailed(CastWebContents* cast_web_contents) {
+  if (client_) {
+    std::unique_ptr<webview::WebviewResponse> response =
+        std::make_unique<webview::WebviewResponse>();
+    auto* event = response->mutable_page_event();
+    event->set_current_page_state(current_state());
+    event->set_resource_load_failed(true);
+    client_->EnqueueSend(std::move(response));
+  }
+}
+
+void WebviewController::Destroy() {
+  // This webview is now abandoned and should close.
+  client_ = nullptr;
+  if (stopped_) {
+    // If the page has been stopped this can be deleted immediately.
+    delete this;
+  } else {
+    // This will eventually call OnPageStopped.
+    cast_web_contents_->ClosePage();
+  }
+}
+
+}  // namespace chromecast

chromecast/browser/webview/webview_controller.h

+// Copyright 2019 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.
+
+#ifndef CHROMECAST_BROWSER_WEBVIEW_WEBVIEW_CONTROLLER_H_
+#define CHROMECAST_BROWSER_WEBVIEW_WEBVIEW_CONTROLLER_H_
+
+#include <memory>
+#include <string>
+
+#include "chromecast/browser/cast_web_contents.h"
+#include "chromecast/browser/webview/proto/webview.pb.h"
+
+namespace aura {
+class Window;
+}  // namespace aura
+
+namespace chromecast {
+class CastWebContents;
+}  // namespace chromecast
+
+namespace content {
+class BrowserContext;
+class WebContents;
+}  // namespace content
+
+namespace chromecast {
+
+// This owns a WebContents and CastWebContents and processes proto commands
+// to allow the web contents to be controlled and embedded.
+class WebviewController : public CastWebContents::Delegate,
+                          public CastWebContents::Observer {
+ public:
+  class Client {
+   public:
+    virtual ~Client() {}
+    virtual void EnqueueSend(
+        std::unique_ptr<webview::WebviewResponse> response) = 0;
+    virtual void OnError(const std::string& error_message) = 0;
+  };
+  WebviewController(content::BrowserContext* browser_context, Client* client);
+  ~WebviewController() override;
+
+  // Cause the controller to be destroyed after giving the webpage a chance to
+  // run unload events. This unsets the client so no more messages will be
+  // sent.
+  void Destroy();
+
+  // Close the page. This will cause a stopped response to eventually be sent.
+  void ClosePage();
+
+  void ProcessRequest(const webview::WebviewRequest& request);
+
+  // Attach this web contents to an aura window as a child.
+  void AttachTo(aura::Window* window, int window_id);
+
+ private:
+  webview::AsyncPageEvent_State current_state();
+
+  void ProcessInputEvent(const webview::InputEvent& ev);
+
+  bool Check(bool condition, const char* error);
+
+  // CastWebContents::Delegate
+  void OnPageStateChanged(CastWebContents* cast_web_contents) override;
+  void OnPageStopped(CastWebContents* cast_web_contents,
+                     int error_code) override;
+
+  // CastWebContents::Observer
+  void ResourceLoadFailed(CastWebContents* cast_web_contents) override;
+
+  Client* client_;  // Not owned.
+  std::unique_ptr<content::WebContents> contents_;
+  std::unique_ptr<CastWebContents> cast_web_contents_;
+  bool stopped_ = false;
+
+  DISALLOW_COPY_AND_ASSIGN(WebviewController);
+};
+
+}  // namespace chromecast
+
+#endif  // CHROMECAST_BROWSER_WEBVIEW_WEBVIEW_CONTROLLER_H_

chromecast/browser/webview/webview_grpc_service.cc

+// Copyright 2019 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 "chromecast/browser/webview/webview_grpc_service.h"
+
+#include <deque>
+#include <mutex>
+
+#include "base/bind.h"
+#include "base/callback.h"
+#include "chromecast/browser/cast_browser_context.h"
+#include "chromecast/browser/cast_browser_process.h"
+#include "chromecast/browser/webview/webview_controller.h"
+#include "components/exo/surface.h"
+#include "components/exo/wm_helper.h"
+#include "third_party/grpc/src/include/grpcpp/grpcpp.h"
+#include "third_party/grpc/src/include/grpcpp/security/server_credentials.h"
+#include "third_party/grpc/src/include/grpcpp/server_builder.h"
+
+namespace chromecast {
+namespace {
+
+aura::Window* FindChildWindowWithID(aura::Window* window, int id) {
+  if (window->GetProperty(exo::kClientSurfaceIdKey) == id)
+    return window;
+  for (auto* w : window->children()) {
+    auto* ret = FindChildWindowWithID(w, id);
+    if (ret)
+      return ret;
+  }
+  return nullptr;
+}
+
+typedef base::RepeatingCallback<void(bool)> GrpcCallback;
+
+// Threading model and life cycle.
+// WebviewRpcInstance creates copies of itself and deletes itself as needed.
+// Instances are deleted when the GRPC Finish request completes and there are
+// no other outstanding read or write operations.
+// Deletion bounces off the webview thread to synchronize with request
+// processing.
+class WebviewRpcInstance : public WebviewController::Client {
+ public:
+  WebviewRpcInstance(webview::WebviewService::AsyncService* service,
+                     grpc::ServerCompletionQueue* cq,
+                     scoped_refptr<base::SingleThreadTaskRunner> task_runner);
+  ~WebviewRpcInstance() override;
+
+ private:
+  void InitComplete(bool ok);
+  void ReadComplete(bool ok);
+  void WriteComplete(bool ok);
+  void FinishComplete(bool ok);
+  bool Initialize();
+
+  void StartRead();
+  void CreateWebview(int app_id, int window_id);
+
+  void ProcessRequestOnWebviewThread(
+      std::unique_ptr<webview::WebviewRequest> request);
+
+  void EnqueueSend(std::unique_ptr<webview::WebviewResponse> response) override;
+  void OnError(const std::string& error_message) override;
+
+  GrpcCallback init_callback_;
+  GrpcCallback read_callback_;
+  GrpcCallback write_callback_;
+  GrpcCallback destroy_callback_;
+
+  grpc::ServerContext ctx_;
+  webview::WebviewService::AsyncService* service_;
+  grpc::ServerCompletionQueue* cq_;
+  std::unique_ptr<webview::WebviewRequest> request_;
+  grpc::ServerAsyncReaderWriter<webview::WebviewResponse,
+                                webview::WebviewRequest>
+      io_;
+  std::unique_ptr<WebviewController> webview_;
+
+  std::mutex send_lock_;
+  bool errored_ = false;
+  std::string error_message_;
+  bool send_pending_ = false;
+  bool destroying_ = false;
+  std::deque<std::unique_ptr<webview::WebviewResponse>> pending_messages_;
+
+  grpc::WriteOptions write_options_;
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebviewRpcInstance);
+};
+
+WebviewRpcInstance::WebviewRpcInstance(
+    webview::WebviewService::AsyncService* service,
+    grpc::ServerCompletionQueue* cq,
+    scoped_refptr<base::SingleThreadTaskRunner> task_runner)
+    : service_(service), cq_(cq), io_(&ctx_), task_runner_(task_runner) {
+  write_options_.clear_buffer_hint();
+  write_options_.clear_corked();
+
+  init_callback_ = base::BindRepeating(&WebviewRpcInstance::InitComplete,
+                                       base::Unretained(this));
+  read_callback_ = base::BindRepeating(&WebviewRpcInstance::ReadComplete,
+                                       base::Unretained(this));
+  write_callback_ = base::BindRepeating(&WebviewRpcInstance::WriteComplete,
+                                        base::Unretained(this));
+  destroy_callback_ = base::BindRepeating(&WebviewRpcInstance::FinishComplete,
+                                          base::Unretained(this));
+
+  service_->RequestCreateWebview(&ctx_, &io_, cq_, cq_, &init_callback_);
+}
+
+WebviewRpcInstance::~WebviewRpcInstance() {
+  DCHECK(destroying_);
+  if (webview_) {
+    webview_.release()->Destroy();
+  }
+}
+
+void WebviewRpcInstance::FinishComplete(bool ok) {
+  // Bounce off of the webview thread to allow it to complete any pending work.
+  destroying_ = true;
+  if (!send_pending_) {
+    task_runner_->DeleteSoon(FROM_HERE, this);
+  }
+}
+
+void WebviewRpcInstance::ProcessRequestOnWebviewThread(
+    std::unique_ptr<webview::WebviewRequest> request) {
+  webview_->ProcessRequest(*request.get());
+}
+
+void WebviewRpcInstance::InitComplete(bool ok) {
+  request_ = std::make_unique<webview::WebviewRequest>();
+  io_.Read(request_.get(), &read_callback_);
+
+  // Create a new instance to handle new requests.
+  // Instances of this class delete themselves.
+  new WebviewRpcInstance(service_, cq_, task_runner_);
+}
+
+void WebviewRpcInstance::ReadComplete(bool ok) {
+  if (!ok) {
+    io_.Finish(grpc::Status(), &destroy_callback_);
+  } else if (webview_) {
+    task_runner_->PostTask(
+        FROM_HERE,
+        base::BindOnce(&WebviewRpcInstance::ProcessRequestOnWebviewThread,
+                       base::Unretained(this),
+                       base::Passed(std::move(request_))));
+
+    request_ = std::make_unique<webview::WebviewRequest>();
+    io_.Read(request_.get(), &read_callback_);
+  } else if (!Initialize()) {
+    io_.Finish(grpc::Status(grpc::FAILED_PRECONDITION, "Failed initialization"),
+               &destroy_callback_);
+  }
+  // In this case initialization is pending and the main webview thread will
+  // start the first read.
+}
+
+bool WebviewRpcInstance::Initialize() {
+  if (request_->type_case() != webview::WebviewRequest::kCreate)
+    return false;
+
+  // This needs to be done on a valid thread.
+  task_runner_->PostTask(
+      FROM_HERE,
+      base::BindOnce(&WebviewRpcInstance::CreateWebview, base::Unretained(this),
+                     request_->create().webview_id(),
+                     request_->create().window_id()));
+  return true;
+}
+
+void WebviewRpcInstance::CreateWebview(int app_id, int window_id) {
+  auto* root_window =
+      exo::WMHelper::GetInstance()->GetRootWindowForNewWindows();
+  auto* surface_window = FindChildWindowWithID(root_window, app_id);
+  if (!surface_window) {
+    OnError("Failed to find valid surface to display webview on");
+    return;
+  }
+
+  content::BrowserContext* browser_context =
+      shell::CastBrowserProcess::GetInstance()->browser_context();
+  webview_ = std::make_unique<WebviewController>(browser_context, this);
+  webview_->AttachTo(surface_window, window_id);
+
+  // Begin reading again.
+  io_.Read(request_.get(), &read_callback_);
+}
+
+void WebviewRpcInstance::WriteComplete(bool ok) {
+  std::unique_lock<std::mutex> l(send_lock_);
+  send_pending_ = false;
+  if (destroying_) {
+    // It is possible for the read & finish to complete while a write is
+    // outstanding, in that case just re-call it to delete this instance.
+    FinishComplete(true);
+  } else if (errored_) {
+    io_.Finish(grpc::Status(grpc::UNKNOWN, error_message_), &destroy_callback_);
+  } else if (!pending_messages_.empty()) {
+    send_pending_ = true;
+    io_.Write(*pending_messages_.front().get(), write_options_,
+              &write_callback_);
+    pending_messages_.pop_front();
+  }
+}
+
+void WebviewRpcInstance::EnqueueSend(
+    std::unique_ptr<webview::WebviewResponse> response) {
+  std::unique_lock<std::mutex> l(send_lock_);
+  if (errored_ || destroying_)
+    return;
+  if (!send_pending_ && pending_messages_.empty()) {
+    send_pending_ = true;
+    io_.Write(*response.get(), write_options_, &write_callback_);
+  } else {
+    pending_messages_.emplace_back(std::move(response));
+  }
+}
+
+void WebviewRpcInstance::OnError(const std::string& error_message) {
+  std::unique_lock<std::mutex> l(send_lock_);
+  errored_ = true;
+  error_message_ = error_message;
+
+  if (!send_pending_)
+    io_.Finish(grpc::Status(grpc::UNKNOWN, error_message_), &destroy_callback_);
+  send_pending_ = true;
+}
+
+}  // namespace
+
+WebviewAsyncService::WebviewAsyncService(
+    scoped_refptr<base::SingleThreadTaskRunner> webview_task_runner)
+    : webview_task_runner_(std::move(webview_task_runner)) {}
+
+WebviewAsyncService::~WebviewAsyncService() {
+  if (server_) {
+    server_->Shutdown();
+    cq_->Shutdown();
+
+    base::PlatformThread::Join(rpc_thread_);
+  }
+}
+
+void WebviewAsyncService::StartWithSocket(const base::FilePath& socket_path) {
+  DCHECK(!server_.get());
+
+  grpc::ServerBuilder builder;
+  builder.AddListeningPort("unix:" + socket_path.value(),
+                           grpc::InsecureServerCredentials());
+  builder.RegisterService(&service_);
+  cq_ = builder.AddCompletionQueue();
+  server_ = builder.BuildAndStart();
+  base::PlatformThread::Create(0, this, &rpc_thread_);
+}
+
+void WebviewAsyncService::ThreadMain() {
+  base::PlatformThread::SetName("CastWebviewGrpcMessagePump");
+
+  void* tag;
+  bool ok;
+  // This self-deletes.
+  new WebviewRpcInstance(&service_, cq_.get(), webview_task_runner_);
+  // This thread is joined when this service is destroyed.
+  while (cq_->Next(&tag, &ok)) {
+    reinterpret_cast<GrpcCallback*>(tag)->Run(ok);
+  }
+}
+
+}  // namespace chromecast

chromecast/browser/webview/webview_grpc_service.h

+// Copyright 2019 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.
+
+#ifndef CHROMECAST_BROWSER_WEBVIEW_WEBVIEW_GRPC_SERVICE_H_
+#define CHROMECAST_BROWSER_WEBVIEW_WEBVIEW_GRPC_SERVICE_H_
+
+#include <string>
+
+#include "base/files/file_path.h"
+#include "base/threading/platform_thread.h"
+#include "base/threading/thread_task_runner_handle.h"
+#include "chromecast/browser/webview/proto/webview.grpc.pb.h"
+#include "third_party/grpc/src/include/grpcpp/server.h"
+
+namespace chromecast {
+
+// This is a service that provides a GRPC interface to create and control
+// webviews. See the proto file for commands.
+class WebviewAsyncService : public base::PlatformThread::Delegate {
+ public:
+  explicit WebviewAsyncService(
+      scoped_refptr<base::SingleThreadTaskRunner> webview_task_runner);
+  ~WebviewAsyncService() override;
+
+  // Start the server listening on an address, eg "localhost:12345".
+  void StartWithSocket(const base::FilePath& socket_path);
+
+ private:
+  void ThreadMain() override;
+
+  base::PlatformThreadHandle rpc_thread_;
+  scoped_refptr<base::SingleThreadTaskRunner> webview_task_runner_;
+  std::unique_ptr<grpc::ServerCompletionQueue> cq_;
+  webview::WebviewService::AsyncService service_;
+  std::unique_ptr<grpc::Server> server_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebviewAsyncService);
+};
+
+}  // namespace chromecast
+
+#endif  // CHROMECAST_BROWSER_WEBVIEW_WEBVIEW_GRPC_SERVICE_H_

chromecast/browser/webview/webview_layout_manager.cc

+// Copyright 2019 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 "chromecast/browser/webview/webview_layout_manager.h"
+
+#include "ui/aura/window.h"
+
+namespace chromecast {
+
+WebviewLayoutManager::WebviewLayoutManager(aura::Window* web_contents_window)
+    : web_contents_window_(web_contents_window) {}
+
+WebviewLayoutManager::~WebviewLayoutManager() {}
+
+void WebviewLayoutManager::OnWindowResized() {
+  web_contents_window_->SetBounds(web_contents_window_->parent()->bounds());
+}
+
+void WebviewLayoutManager::OnWindowAddedToLayout(aura::Window* child) {}
+
+void WebviewLayoutManager::OnWillRemoveWindowFromLayout(aura::Window* child) {}
+
+void WebviewLayoutManager::OnWindowRemovedFromLayout(aura::Window* child) {}
+
+void WebviewLayoutManager::OnChildWindowVisibilityChanged(aura::Window* child,
+                                                          bool visible) {}
+
+void WebviewLayoutManager::SetChildBounds(aura::Window* child,
+                                          const gfx::Rect& requested_bounds) {
+  SetChildBoundsDirect(child, requested_bounds);
+}
+
+}  // namespace chromecast

chromecast/browser/webview/webview_layout_manager.h

+// Copyright 2019 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.
+
+#ifndef CHROMECAST_BROWSER_WEBVIEW_WEBVIEW_LAYOUT_MANAGER_H_
+#define CHROMECAST_BROWSER_WEBVIEW_WEBVIEW_LAYOUT_MANAGER_H_
+
+#include "base/macros.h"
+#include "ui/aura/layout_manager.h"
+
+namespace chromecast {
+
+// Resizes the provided window to be the parent window's size.
+class WebviewLayoutManager : public aura::LayoutManager {
+ public:
+  explicit WebviewLayoutManager(aura::Window* web_contents_window);
+  ~WebviewLayoutManager() override;
+
+  void OnWindowResized() override;
+  void OnWindowAddedToLayout(aura::Window* child) override;
+  void OnWillRemoveWindowFromLayout(aura::Window* child) override;
+  void OnWindowRemovedFromLayout(aura::Window* child) override;
+  void OnChildWindowVisibilityChanged(aura::Window* child,
+                                      bool visible) override;
+  void SetChildBounds(aura::Window* child,
+                      const gfx::Rect& requested_bounds) override;
+
+ private:
+  aura::Window* web_contents_window_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebviewLayoutManager);
+};
+
+}  // namespace chromecast
+
+#endif  // CHROMECAST_BROWSER_WEBVIEW_WEBVIEW_LAYOUT_MANAGER_H_

third_party/grpc/BUILD.gn

@@ -33,8 +33,11 @@ config("nanopb_config") {
 # The gRPC library. Note that server side code will not be built. You probably
 # want to use cc_grpc_library() from grpc_library.gni directly.
 static_library("grpcpp") {
-  # This is currently only used by remoting.
-  visibility = [ "//remoting/*" ]
+  # This is currently only used by remoting and chromecast.
+  visibility = [
+    "//chromecast/*",
+    "//remoting/*",
+  ]
   sources = [
     "src/src/cpp/client/channel_cc.cc",
     "src/src/cpp/client/client_context.cc",