headless: Initial headless embedder API implementation

headless/lib/browser/headless_browser_context.h

+// 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.
+
+#ifndef HEADLESS_LIB_BROWSER_HEADLESS_BROWSER_CONTEXT_H_
+#define HEADLESS_LIB_BROWSER_HEADLESS_BROWSER_CONTEXT_H_
+
+#include "base/files/file_path.h"
+#include "content/public/browser/browser_context.h"
+#include "content/public/browser/content_browser_client.h"
+#include "content/public/browser/resource_context.h"
+#include "headless/lib/browser/headless_url_request_context_getter.h"
+#include "headless/public/headless_browser.h"
+
+namespace headless {
+
+class HeadlessBrowserContext : public content::BrowserContext {
+ public:
+  explicit HeadlessBrowserContext(const HeadlessBrowser::Options& options);
+  ~HeadlessBrowserContext() override;
+
+  // BrowserContext implementation:
+  scoped_ptr<content::ZoomLevelDelegate> CreateZoomLevelDelegate(
+      const base::FilePath& partition_path) override;
+  base::FilePath GetPath() const override;
+  bool IsOffTheRecord() const override;
+  net::URLRequestContextGetter* GetRequestContext() override;
+  net::URLRequestContextGetter* GetRequestContextForRenderProcess(
+      int renderer_child_id) override;
+  net::URLRequestContextGetter* GetMediaRequestContext() override;
+  net::URLRequestContextGetter* GetMediaRequestContextForRenderProcess(
+      int renderer_child_id) override;
+  net::URLRequestContextGetter* GetMediaRequestContextForStoragePartition(
+      const base::FilePath& partition_path,
+      bool in_memory) override;
+  content::ResourceContext* GetResourceContext() override;
+  content::DownloadManagerDelegate* GetDownloadManagerDelegate() override;
+  content::BrowserPluginGuestManager* GetGuestManager() override;
+  storage::SpecialStoragePolicy* GetSpecialStoragePolicy() override;
+  content::PushMessagingService* GetPushMessagingService() override;
+  content::SSLHostStateDelegate* GetSSLHostStateDelegate() override;
+  content::PermissionManager* GetPermissionManager() override;
+  content::BackgroundSyncController* GetBackgroundSyncController() override;
+
+  // Clears |protocol_handlers| but does not take ownership of it.
+  scoped_refptr<net::URLRequestContextGetter> CreateRequestContext(
+      content::ProtocolHandlerMap* protocol_handlers,
+      content::URLRequestInterceptorScopedVector request_interceptors);

[Ryan Sleevi, 2016/02/22 22:01:21]

STYLE: The documentation for this (which appears to be a class method, given the
lack of override) is lacking.

[Sami, 2016/02/23 20:19:07]

Agreed -- refactored this into HeadlessContentBrowserClient.

+
+  const HeadlessBrowser::Options& options() const { return options_; }
+
+ private:
+  // Contains net::URLRequestContextGetter required for resource loading.
+  class HeadlessResourceContext : public content::ResourceContext {

[Ryan Sleevi, 2016/02/22 21:11:13]

Why don't you simply forward declare this class, avoiding leaking your
abstraction into this header.

[Sami, 2016/02/23 20:19:07]

Done.

+   public:
+    HeadlessResourceContext();
+    ~HeadlessResourceContext() override;
+
+    // ResourceContext implementation:
+    net::HostResolver* GetHostResolver() override;
+    net::URLRequestContext* GetRequestContext() override;
+
+    void set_url_request_context_getter(
+        scoped_refptr<net::URLRequestContextGetter> getter) {
+      getter_ = getter;
+    }
+
+   private:
+    scoped_refptr<net::URLRequestContextGetter> getter_;
+
+    DISALLOW_COPY_AND_ASSIGN(HeadlessResourceContext);
+  };
+
+  // Used by HeadlessBrowserContext to initiate and set different types of
+  // URLRequestContextGetter.

[Ryan Sleevi, 2016/02/22 22:01:21]

Document that it does, not how it's used.
https://google.github.io/styleguide/cppguide.html#Function_Comments

[Sami, 2016/02/23 20:19:07]

Removed.

+  HeadlessURLRequestContextGetter* CreateURLRequestContextGetter(
+      content::ProtocolHandlerMap* protocol_handlers,
+      content::URLRequestInterceptorScopedVector request_interceptors);
+
+  void set_url_request_context_getter(
+      scoped_refptr<HeadlessURLRequestContextGetter> getter) {
+    url_request_getter_ = getter;

[Ryan Sleevi, 2016/02/22 21:11:13]

This is a weird API that you have two different classes for holding on to the
_getter

[Sami, 2016/02/23 20:19:07]

Agreed, I've now only made one of them hang on to the getter. FWIW the classes
can't be completely merged because content::ResourceContext needs to be
destroyed on the IO thread:

https://code.google.com/p/chromium/codesearch#chromium/src/content/public/bro...

(Added a comment.)

+  }
+
+  // Performs initialization of the HeadlessBrowserContext while IO is still
+  // allowed on the current thread.
+  void InitWhileIOAllowed();
+
+  base::FilePath path_;
+  scoped_ptr<HeadlessResourceContext> resource_context_;
+  scoped_refptr<net::URLRequestContextGetter> url_request_getter_;
+  HeadlessBrowser::Options options_;
+
+  DISALLOW_COPY_AND_ASSIGN(HeadlessBrowserContext);
+};
+
+}  // namespace headless
+
+#endif  // HEADLESS_LIB_BROWSER_HEADLESS_BROWSER_CONTEXT_H_