[ntp] Add flag to disable the logo (reland)

Makes the logo Finch-configurable. Flag is enabled by default.

This is a reland of 660b7591 with a fix
for the msan builder. See crbug/1169070 for more details.

Original change's info:
> Bug: 1168361
> Change-Id: Ie9fbeebb5f88fcf6ca2d6a418759f65e61d3231e
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2639153
> Commit-Queue: Tibor Goldschwendt <tiborg@chromium.org>
> Reviewed-by: Esmael Elmoslimany <aee@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#845490}

Bug: 1168361
Fixed: 1169070
Change-Id: I9f038b06cfd7551bf0acb94a7ac08cb8d49d7095
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2643179
Auto-Submit: Tibor Goldschwendt <tiborg@chromium.org>
Commit-Queue: Tibor Goldschwendt <tiborg@chromium.org>
Commit-Queue: Esmael Elmoslimany <aee@chromium.org>
Reviewed-by: Esmael Elmoslimany <aee@chromium.org>
Cr-Commit-Position: refs/heads/master@{#845896}

chrome/browser/resources/new_tab_page/app.html

@@ -253,9 +253,13 @@
         hidden$="[[!oneGoogleBarLoaded_]]">
     </ntp-iframe>
   </template>
+  <!-- TODO(crbug.com/1168361): Instead of hidden$="[[!logoEnabled_]]" it would
+       be nicer to use a dom-if. However, that breaks
+       StartupBrowserCreatorPickerNoParamsTest.ShowPickerWhenAlreadyLaunched on
+       the msan builder. See crbug.com/1169070. -->
   <ntp-logo id="logo" doodle-allowed$="[[doodleAllowed_]]"
       single-colored$="[[singleColoredLogo_]]" dark="[[theme_.isDark]]"
-      background-color="[[backgroundColor_]]">
+      background-color="[[backgroundColor_]]" hidden$="[[!logoEnabled_]]">
   </ntp-logo>
   <ntp-realbox id="realbox" on-open-voice-search="onOpenVoiceSearch_"
       theme="[[theme_.searchBox]]" shown$="[[realboxShown_]]">

chrome/browser/resources/new_tab_page/app.js

@@ -190,6 +190,12 @@ class AppElement extends PolymerElement {
         computed: 'computeRealboxShown_(theme_)',
       },
 
+      /** @private */
+      logoEnabled_: {
+        type: Boolean,
+        value: () => loadTimeData.getBoolean('logoEnabled'),
+      },
+
       /** @private */
       shortcutsEnabled_: {
         type: Boolean,

chrome/browser/ui/webui/new_tab_page/new_tab_page_ui.cc

@@ -100,6 +100,8 @@ content::WebUIDataSource* CreateNewTabPageUiHtmlSource(Profile* profile) {
       base::FeatureList::IsEnabled(ntp_features::kWebUIThemeModeDoodles));
   source->AddBoolean("shortcutsEnabled",
                      base::FeatureList::IsEnabled(ntp_features::kNtpShortcuts));
+  source->AddBoolean("logoEnabled",
+                     base::FeatureList::IsEnabled(ntp_features::kNtpLogo));
   source->AddBoolean(
       "middleSlotPromoEnabled",
       base::FeatureList::IsEnabled(ntp_features::kNtpMiddleSlotPromo));

components/search/ntp_features.cc

@@ -75,6 +75,9 @@ const base::Feature kWebUI{"NtpWebUI", base::FEATURE_ENABLED_BY_DEFAULT};
 const base::Feature kWebUIThemeModeDoodles{"WebUIThemeModeDoodles",
                                            base::FEATURE_ENABLED_BY_DEFAULT};
 
+// If enabled, logo will be shown.
+const base::Feature kNtpLogo{"NtpLogo", base::FEATURE_ENABLED_BY_DEFAULT};
+
 // If enabled, shortcuts will be shown.
 const base::Feature kNtpShortcuts{"NtpShortcuts",
                                   base::FEATURE_ENABLED_BY_DEFAULT};

components/search/ntp_features.h

@@ -26,6 +26,7 @@ extern const base::Feature kRealboxMatchOmniboxTheme;
 extern const base::Feature kRealboxUseGoogleGIcon;
 extern const base::Feature kWebUI;
 extern const base::Feature kWebUIThemeModeDoodles;
+extern const base::Feature kNtpLogo;
 extern const base::Feature kNtpShortcuts;
 extern const base::Feature kNtpMiddleSlotPromo;
 extern const base::Feature kModules;