Revert "Make sure kNotificationId and kAppId are mutual exclusive on Windows"

This reverts commit 44e2fc52.

Reason for revert: <CL title/description is inaccurate>

Original change's description:
> Make sure kNotificationId and kAppId are mutual exclusive on Windows
> 
> Bug: 734095
> Change-Id: I08275fff11aef97c3265a6832dc1485b4ef19b61
> Reviewed-on: https://chromium-review.googlesource.com/1038432
> Commit-Queue: Xi Cheng <chengx@chromium.org>
> Reviewed-by: Tommy Martino <tmartino@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#555986}

TBR=tmartino@chromium.org,chengx@chromium.org

Change-Id: I050712e720d65ab5b59ef67752c0c1bd3bbbbe02
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 734095
Reviewed-on: https://chromium-review.googlesource.com/1044569Reviewed-by: Xi Cheng <chengx@chromium.org>
Commit-Queue: Xi Cheng <chengx@chromium.org>
Cr-Commit-Position: refs/heads/master@{#556085}

chrome/browser/ui/startup/startup_browser_creator_impl.cc

@@ -373,20 +373,6 @@ bool StartupBrowserCreatorImpl::Launch(Profile* profile,
   DCHECK(profile);
   profile_ = profile;
 
-#if defined(OS_WIN)
-  // If the command line has the kNotificationLaunchId switch, then this
-  // Launch() call is from notification_helper.exe to process toast activation.
-  // Delegate to the notification system; do not open a browser window here.
-  if (command_line_.HasSwitch(switches::kNotificationLaunchId)) {
-    DCHECK(!command_line_.HasSwitch(switches::kAppId));
-    if (NotificationPlatformBridgeWin::HandleActivation(command_line_)) {
-      RecordLaunchModeHistogram(LM_WIN_PLATFORM_NOTIFICATION);
-      return true;
-    }
-    return false;
-  }
-#endif  // defined(OS_WIN)
-
   if (command_line_.HasSwitch(switches::kAppId)) {
     std::string app_id = command_line_.GetSwitchValueASCII(switches::kAppId);
     const Extension* extension = GetPlatformApp(profile, app_id);
@@ -404,6 +390,19 @@ bool StartupBrowserCreatorImpl::Launch(Profile* profile,
     }
   }
 
+#if defined(OS_WIN)
+  // If the command line has the kNotificationLaunchId switch, then this
+  // Launch() call is from notification_helper.exe to process toast activation.
+  // Delegate to the notification system; do not open a browser window here.
+  if (command_line_.HasSwitch(switches::kNotificationLaunchId)) {
+    if (NotificationPlatformBridgeWin::HandleActivation(command_line_)) {
+      RecordLaunchModeHistogram(LM_WIN_PLATFORM_NOTIFICATION);
+      return true;
+    }
+    return false;
+  }
+#endif  // defined(OS_WIN)
+
   // Open the required browser windows and tabs. First, see if
   // we're being run as an application window. If so, the user
   // opened an app shortcut.  Don't restore tabs or open initial