Reland "serial: Add option to switch enumeration methods"

This reverts commit 412cff1e7077722f0f3dfb16602c2d154bf5b021.

Reason for revert: Figured out why the change had no effect.

Original change's description:
> Revert "serial: Add option to switch enumeration methods"
>
> This reverts commit fdbcb258e0dcc2eccf6927aa4c77f6af56fc0b0e.
>
> Reason for revert: The new flag didn't resolve the issue.
>
> Original change's description:
> > serial: Add option to switch enumeration methods
> > 
> > A potential solution for issue 1119497 is to switch from enumerating
> > devices implementing GUID_DEVINTERFACE_COMPORT to using the "bus
> > enumerator" identified by GUID_DEVINTERFACE_SERENUM_BUS_ENUMERATOR.
> > 
> > I'm putting this behind a flag so that developers can try it out in
> > canary-channel. If it works I can enable it by default and keep the flag
> > around for a couple releases in case it causes other problems.
> > 
> > Bug: 1119497
> > Change-Id: Icad9008799ed331c3da15e5a70e0184144c47a58
> > Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2417460
> > Commit-Queue: Ovidio de Jesús Ruiz-Henríquez <[email protected]>
> > Reviewed-by: Ovidio de Jesús Ruiz-Henríquez <[email protected]>
> > Auto-Submit: Reilly Grant <[email protected]>
> > Cr-Commit-Position: refs/heads/master@{#808368}
>
> [email protected],[email protected]
>
> # Not skipping CQ checks because original CL landed > 1 day ago.
>
> Bug: 1119497
> Change-Id: I3e39d5de932e94b980e7fb5f6de71a2cfa45b0f3
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2423053
> Reviewed-by: Reilly Grant <[email protected]>
> Commit-Queue: Reilly Grant <[email protected]>
> Cr-Commit-Position: refs/heads/master@{#809207}

Bug: 1119497
Change-Id: I39bb97d5e1cc5ca5dc971ba2dfad3e9eb987141d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2432005
Commit-Queue: Reilly Grant <[email protected]>
Reviewed-by: Reilly Grant <[email protected]>
Reviewed-by: Ovidio de Jesús Ruiz-Henríquez <[email protected]>
Cr-Commit-Position: refs/heads/master@{#810925}
diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
index 3d50a6c..3910e94 100644
--- a/chrome/browser/flag_descriptions.cc
+++ b/chrome/browser/flag_descriptions.cc
@@ -3425,6 +3425,11 @@
 const char kUseAngleD3D9[] = "D3D9";
 const char kUseAngleD3D11on12[] = "D3D11on12";
 
+const char kUseSerialBusEnumeratorName[] = "Use system serial port enumerator";
+const char kUseSerialBusEnumeratorDescription[] =
+    "Use the system-supplied enumerator for serial port devices instead of "
+    "enumerating devices implementing the COM port interface.";
+
 const char kUseWinrtMidiApiName[] = "Use Windows Runtime MIDI API";
 const char kUseWinrtMidiApiDescription[] =
     "Use Windows Runtime MIDI API for WebMIDI (effective only on Windows 10 or "