Move ChromeOS login media access logic into a MediaAccessHandler

chrome/browser/media/chromeos_login_media_access_handler.cc

+// Copyright 2017 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 "chrome/browser/media/chromeos_login_media_access_handler.h"
+
+#include "base/values.h"
+#include "chrome/browser/chromeos/login/ui/login_display_host.h"
+#include "chrome/browser/chromeos/login/ui/webui_login_view.h"
+#include "chrome/browser/chromeos/settings/cros_settings.h"
+#include "chrome/common/url_constants.h"
+#include "chromeos/settings/cros_settings_names.h"
+#include "components/content_settings/core/common/content_settings_pattern.h"
+
+ChromeOSLoginMediaAccessHandler::ChromeOSLoginMediaAccessHandler() {}
+
+ChromeOSLoginMediaAccessHandler::~ChromeOSLoginMediaAccessHandler() {}
+
+bool ChromeOSLoginMediaAccessHandler::SupportsStreamType(
+    content::WebContents* web_contents,
+    const content::MediaStreamType type,
+    const extensions::Extension* extension) {
+  chromeos::LoginDisplayHost* login_display_host =

[achuithb, 2017/04/05 00:55:36]

Can we add a DCHECK(web_contents);

[raymes, 2017/04/10 00:16:49]

Done.

[raymes, 2017/04/10 02:42:28]

It turns out this can be nullptr, so I've added a check to return false in that
case.

+      chromeos::LoginDisplayHost::default_host();
+  chromeos::WebUILoginView* webui_login_view =
+      login_display_host ? login_display_host->GetWebUILoginView() : nullptr;
+  content::WebContents* login_web_contents =
+      webui_login_view ? webui_login_view->GetWebContents() : nullptr;
+  return web_contents == login_web_contents;
+}
+
+bool ChromeOSLoginMediaAccessHandler::CheckMediaAccessPermission(
+    content::WebContents* web_contents,
+    const GURL& security_origin,
+    content::MediaStreamType type,
+    const extensions::Extension* extension) {
+  if (type != content::MEDIA_DEVICE_VIDEO_CAPTURE)
+    return false;
+
+  // When creating new user (including supervised user), we must be able to use
+  // the camera to capture a user image.
+  if (security_origin.spec() == chrome::kChromeUIOobeURL)

[emaxx, 2017/04/06 02:41:47]

nit: #include "url/gurl.h"

[raymes, 2017/04/10 00:16:49]

Done.

+    return true;
+
+  const chromeos::CrosSettings* const settings = chromeos::CrosSettings::Get();
+  if (!settings)
+    return false;
+
+  // The following checks are for SAML logins.
+  const base::Value* const raw_list_value =
+      settings->GetPref(chromeos::kLoginVideoCaptureAllowedUrls);
+  if (!raw_list_value)
+    return false;
+
+  const base::ListValue* list_value;
+  const bool is_list = raw_list_value->GetAsList(&list_value);
+  DCHECK(is_list);
+  for (const auto& base_value : *list_value) {
+    std::string value;

[emaxx, 2017/04/06 02:41:47]

nit #include <string>

[raymes, 2017/04/10 00:16:49]

Done.

+    if (base_value->GetAsString(&value)) {
+      const ContentSettingsPattern pattern =
+          ContentSettingsPattern::FromString(value);
+      // Force administrators to specify more-specific patterns by ignoring the
+      // global wildcard pattern.
+      if (pattern == ContentSettingsPattern::Wildcard()) {
+        VLOG(0) << "Ignoring wildcard URL pattern: " << value;

[achuithb, 2017/04/05 00:55:36]

Should this be VLOG(1)?

[emaxx, 2017/04/06 02:41:47]

nit: #include "base/logging.h"

[raymes, 2017/04/10 00:16:49]

Done.

[raymes, 2017/04/10 00:16:49]

Done.

+        continue;
+      }
+      if (pattern.IsValid() && pattern.Matches(security_origin))
+        return true;
+    }
+  }
+  return false;
+}
+
+void ChromeOSLoginMediaAccessHandler::HandleRequest(
+    content::WebContents* web_contents,
+    const content::MediaStreamRequest& request,
+    const content::MediaResponseCallback& callback,
+    const extensions::Extension* extension) {
+  bool audio_allowed = false;
+  bool video_allowed =
+      request.video_type == content::MEDIA_DEVICE_VIDEO_CAPTURE &&
+      CheckMediaAccessPermission(web_contents, request.security_origin,
+                                 content::MEDIA_DEVICE_VIDEO_CAPTURE,
+                                 extension);
+
+  CheckDevicesAndRunCallback(web_contents, request, callback, audio_allowed,
+                             video_allowed);
+}