ui/display: make kUseHDRTransferFunction a base::Feature and disable it

This CL changes the switch kEnableUseHDRTransferFunction to a
base::FeatureFlag kUseHDRTransferFunction which is more adequate
to after-launch, where users will like to see the hdr-ness state
as "disabled" "enabled" or "default", as opposed to having a naked
flag where the correspondence chrome:flags<->feature status is
non-intuitive.

This CL also disables kUseHDRTransferFunction with the idea of fixing
the current quirks (e.g. b/158777601, b/158781255, b/159224397) and
enabling it very soon.

This CL also takes the chance to remove the unused entry
display::features::kUseMonitorColorSpace.

[email protected] for chrome_restart_request.cc

Bug: 958166, b:159919063
Change-Id: I10e48aee423924cfa7eea7c72d5455f1ffe72648
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2276516
Commit-Queue: Miguel Casas <[email protected]>
Reviewed-by: Jao-ke Chin-Lee <[email protected]>
Reviewed-by: Daniele Castagna <[email protected]>
Cr-Commit-Position: refs/heads/master@{#784790}
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 4312c50..c37933c4 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -2004,8 +2004,8 @@
 extern const char kDisplayIdentificationName[];
 extern const char kDisplayIdentificationDescription[];
 
-extern const char kEnableUseHDRTransferFunctionName[];
-extern const char kEnableUseHDRTransferFunctionDescription[];
+extern const char kUseHDRTransferFunctionName[];
+extern const char kUseHDRTransferFunctionDescription[];
 
 extern const char kDisableOfficeEditingComponentAppName[];
 extern const char kDisableOfficeEditingComponentAppDescription[];