extensions: remove system web app special handling

System web app launch is migrated to web app launch after BMO project.

This CL removes the if branch for intercepting SWA launch in extension
application launch procedure.

Bug: 1065748
Change-Id: Ica93bd3e06eda96d15a514fbe8da24c2793becfc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2612304Reviewed-by: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Reviewed-by: Ben Wells <benwells@chromium.org>
Auto-Submit: Jiewei Qian  <qjw@chromium.org>
Commit-Queue: Ben Wells <benwells@chromium.org>
Cr-Commit-Position: refs/heads/master@{#840839}

chrome/browser/ui/extensions/application_launch.cc

@@ -37,14 +37,12 @@
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/extensions/extension_enable_flow.h"
 #include "chrome/browser/ui/extensions/extension_enable_flow_delegate.h"
-#include "chrome/browser/ui/web_applications/system_web_app_ui_utils.h"
 #include "chrome/browser/ui/web_applications/web_app_launch_manager.h"
 #include "chrome/browser/ui/web_applications/web_app_launch_utils.h"
 #include "chrome/browser/web_applications/components/os_integration_manager.h"
 #include "chrome/browser/web_applications/components/web_app_helpers.h"
 #include "chrome/browser/web_applications/components/web_app_provider_base.h"
 #include "chrome/browser/web_applications/components/web_app_tab_helper_base.h"
-#include "chrome/browser/web_applications/system_web_app_manager.h"
 #include "chrome/browser/web_launch/web_launch_files_helper.h"
 #include "chrome/common/extensions/manifest_handlers/app_launch_info.h"
 #include "chrome/common/url_constants.h"
@@ -333,15 +331,6 @@ WebContents* OpenEnabledApplication(Profile* profile,
 
   GURL url = UrlForExtension(extension, profile, params);
 
-  // System Web Apps go through their own launch path.
-  base::Optional<web_app::SystemAppType> system_app_type =
-      web_app::GetSystemWebAppTypeForAppId(profile, extension->id());
-  if (system_app_type) {
-    Browser* browser = web_app::LaunchSystemWebApp(profile, *system_app_type,
-                                                   url, std::move(params));
-    return browser->tab_strip_model()->GetActiveWebContents();
-  }
-
   // Record v1 app launch. Platform app launch is recorded when dispatching
   // the onLaunched event.
   prefs->SetLastLaunchTime(extension->id(), base::Time::Now());