Revert "dpwas: deprecate existing display_overrides field in proto"

This reverts commit 3ce00758.

Reason for revert: Keeping single enum

Original change's description:
> dpwas: deprecate existing display_overrides field in proto
>
> Feedback provided in a different CL (2375597: dpwas: Add
> window-controls-overlay as a new display mode |
> https://chromium-review.googlesource.com/c/chromium/src/+/2375597)
> and in https://github.com/w3c/manifest/pull/932 is that we need a
> way to say new display modes are allowed in display_override but
> not display.
>
> The plan is to introduce a new enum EnhancedDisplayMode, and
> display_override should be:
>   sequence<DisplayModeType or EnhancedDisplayModeType>.
>
> To support that, this CL deprecates the existing display_override field,
> and renames it. Renaming here should be fine, as long as we don't use
> JSON serialization. Once the new field has landed, we will remove
> this field, and mark it reserved so that future users don't reuse
> the field.
>
> Explainer: https://github.com/WICG/display-override/blob/master/explainer.md
> Design document: https://docs.google.com/document/d/1hEmbGVHMN38q1YTaaGccQ-Y5CHr7xIURYPRWXTuvZLo/edit?usp=sharing
> I2P: https://groups.google.com/a/chromium.org/d/topic/blink-dev/WvIeZT8uSzw/discussion
> Manifest w3c PR: https://github.com/w3c/manifest/pull/932
>
> Bug: 1092667
> Change-Id: Ifbc0160a88263d4994d138f99921371ceea2bcb8
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2436417
> Commit-Queue: Mike Jackson <mjackson@microsoft.com>
> Reviewed-by: Alexey Baskakov <loyso@chromium.org>
> Reviewed-by: Daniel Murphy <dmurph@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#811932}

TBR=dmurph@chromium.org,loyso@chromium.org,mjackson@microsoft.com

Change-Id: Ie953a019c6c9d0dc7e90ea2fcf639325460e8e11
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1092667
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2441147Reviewed-by: Daniel Murphy <dmurph@chromium.org>
Commit-Queue: Daniel Murphy <dmurph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812127}

chrome/browser/web_applications/proto/web_app.proto

@@ -135,10 +135,8 @@ message WebAppProto {
 
   optional uint32 background_color = 21;
 
-  // Deprecated 9/28/2020. A list of display modes specified in app manifest.
-  // TODO (crbug.com/1092667): Replace with RESERVED
-  repeated DisplayMode deprecated_display_mode_override = 22
-      [deprecated = true];
+  // A list of display modes specified in app manifest.
+  repeated DisplayMode display_mode_override = 22;
 
   // A list of icon sizes we successfully downloaded to store on disk, for icons
   // that are designed for masking (ie. IconPurpose::MASKABLE). See also:

chrome/browser/web_applications/web_app_database.cc

@@ -166,7 +166,7 @@ std::unique_ptr<WebAppProto> WebAppDatabase::CreateWebAppProto(
   }
 
   for (const DisplayMode& display_mode : web_app.display_mode_override()) {
-    local_data->add_deprecated_display_mode_override(
+    local_data->add_display_mode_override(
         ToWebAppProtoDisplayMode(display_mode));
   }
 
@@ -404,9 +404,8 @@ std::unique_ptr<WebApp> WebAppDatabase::CreateWebApp(
     web_app->SetDisplayMode(ToMojomDisplayMode(local_data.display_mode()));
 
   std::vector<DisplayMode> display_mode_override;
-  for (int i = 0; i < local_data.deprecated_display_mode_override_size(); i++) {
-    WebAppProto::DisplayMode display_mode =
-        local_data.deprecated_display_mode_override(i);
+  for (int i = 0; i < local_data.display_mode_override_size(); i++) {
+    WebAppProto::DisplayMode display_mode = local_data.display_mode_override(i);
     display_mode_override.push_back(ToMojomDisplayMode(display_mode));
   }
   web_app->SetDisplayModeOverride(std::move(display_mode_override));