Remove the MojoChannelMac signal file clean-up logic.

This has been present for two milestones, which should be sufficient to
clean up a harmless file.

Bug: 973882
Change-Id: I9506284bc480ea3d38fa5e2dd21491355857e9c0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1731017Reviewed-by: Dominick Ng <dominickn@chromium.org>
Commit-Queue: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#683425}

chrome/browser/apps/app_shim/app_shim_host_manager_mac.mm

@@ -79,12 +79,6 @@ void AppShimHostManager::InitOnBackgroundThread() {
       std::make_unique<apps::MachBootstrapAcceptor>(name_fragment, this);
   mach_acceptor_->Start();
 
-  // TODO(rsesek): Delete this after a little while, to ensure everything
-  // is cleaned up.
-  base::FilePath mojo_channel_mac_signal_file =
-      user_data_dir.Append(app_mode::kMojoChannelMacSignalFile);
-  base::DeleteFile(mojo_channel_mac_signal_file, false);
-
   // Create a symlink containing the current version string. This allows the
   // shim to load the same framework version as the currently running Chrome
   // process.

chrome/common/mac/app_mode_common.h

@@ -43,13 +43,6 @@ constexpr mach_msg_id_t kBootstrapMsgId = 'apps';
 // of the full profile directory path.
 extern const char kAppShimBootstrapNameFragment[];
 
-// TODO(rsesek): Delete this after ensuring the file has been cleaned up.
-// The name of a file placed in the profile directory to indicate that app
-// shims should connect over Mach IPC rather than a UNIX domain socket. If
-// a file named this does not exist, app shims will fall back to the UNIX
-// domain socket.
-extern const char kMojoChannelMacSignalFile[];
-
 // A symlink used to store the version string of the currently running Chrome.
 // The shim will read this to determine which version of the framework to load.
 extern const char kRunningChromeVersionSymlinkName[];

chrome/common/mac/app_mode_common.mm

@@ -10,7 +10,6 @@
 namespace app_mode {
 
 const char kAppShimBootstrapNameFragment[] = "apps";
-const char kMojoChannelMacSignalFile[] = "apps_use_mojo_channel_mac";
 
 const char kRunningChromeVersionSymlinkName[] = "RunningChromeVersion";