headless: Initial headless embedder API implementation

headless/lib/browser/headless_browser_impl.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 "headless/lib/browser/headless_browser_impl.h"
+
+#include "base/thread_task_runner_handle.h"
+#include "content/public/app/content_main.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/web_contents.h"
+#include "headless/lib/browser/headless_browser_context.h"
+#include "headless/lib/browser/headless_browser_main_parts.h"
+#include "headless/lib/browser/headless_web_contents_impl.h"
+#include "headless/lib/headless_content_main_delegate.h"
+#include "ui/aura/env.h"
+#include "ui/aura/window_tree_host.h"
+#include "ui/gfx/geometry/size.h"
+
+namespace headless {
+
+HeadlessBrowserImpl::~HeadlessBrowserImpl() {}
+
+scoped_ptr<HeadlessWebContents> HeadlessBrowserImpl::CreateWebContents(
+    const gfx::Size& size) {
+  DCHECK(BrowserMainThread()->BelongsToCurrentThread());
+  return make_scoped_ptr(new HeadlessWebContentsImpl(
+      browser_context(), window_tree_host_->window(), size));
+}
+
+scoped_refptr<base::SingleThreadTaskRunner>
+HeadlessBrowserImpl::BrowserMainThread() const {
+  return content::BrowserThread::GetMessageLoopProxyForThread(
+      content::BrowserThread::UI);
+}
+
+void HeadlessBrowserImpl::Shutdown() {
+  DCHECK(BrowserMainThread()->BelongsToCurrentThread());
+  BrowserMainThread()->PostTask(FROM_HERE,
+                                base::MessageLoop::QuitWhenIdleClosure());
+}
+
+HeadlessBrowserContext* HeadlessBrowserImpl::browser_context() const {
+  DCHECK(BrowserMainThread()->BelongsToCurrentThread());
+  DCHECK(browser_main_parts());
+  return browser_main_parts()->browser_context();
+}
+
+HeadlessBrowserMainParts* HeadlessBrowserImpl::browser_main_parts() const {
+  DCHECK(BrowserMainThread()->BelongsToCurrentThread());
+  return browser_main_parts_;
+}
+
+void HeadlessBrowserImpl::set_browser_main_parts(
+    HeadlessBrowserMainParts* browser_main_parts) {
+  DCHECK(!browser_main_parts_);
+  browser_main_parts_ = browser_main_parts;
+}
+
+void HeadlessBrowserImpl::RunOnStartCallback() {
+  DCHECK(aura::Env::GetInstance());
+  window_tree_host_.reset(aura::WindowTreeHost::Create(gfx::Rect()));
+  window_tree_host_->InitHost();
+
+  DCHECK(!on_start_callback_.is_null());

[Ryan Sleevi, 2016/02/25 22:04:36]

? Isn't this better dchecked in the HeadlessBrowserImpl ctor (see the recent
DCHECK discussion on chromium-dev)

[Sami, 2016/02/26 18:49:16]

Agreed & done.

+  on_start_callback_.Run(this);
+  on_start_callback_ = base::Callback<void(HeadlessBrowser*)>();
+}
+
+HeadlessBrowserImpl::HeadlessBrowserImpl(
+    const base::Callback<void(HeadlessBrowser*)>& on_start_callback,
+    const HeadlessBrowser::Options& options)
+    : on_start_callback_(on_start_callback),
+      options_(options),
+      browser_main_parts_(nullptr) {}
+
+int HeadlessBrowserMain(
+    const HeadlessBrowser::Options& options,
+    const base::Callback<void(HeadlessBrowser*)>& on_browser_start_callback) {
+  scoped_ptr<HeadlessBrowserImpl> browser(
+      new HeadlessBrowserImpl(on_browser_start_callback, options));
+
+  // TODO(skyostil): Implement custom message pumps.
+  DCHECK(!options.message_pump);
+
+  headless::HeadlessContentMainDelegate delegate(std::move(browser));
+  content::ContentMainParams params(&delegate);
+  params.argc = options.argc;
+  params.argv = options.argv;
+  return content::ContentMain(params);
+}
+
+}  // namespace headless