Bug 1804657 - Remove dead code related to having native theme in content on Linux. r=stransky

Since the headless work (bug 1129492 and co) we realistically have no
way of rendering native scrollbars in any meaningful way. Remove dead
code that used to support using a different GTK theme on content.

Differential Revision: https://phabricator.services.mozilla.com/D179616

modules/libpref/init/StaticPrefList.yaml

@@ -15405,12 +15405,6 @@
   mirror: always
 #endif
 
-# Whether to allow gtk dark themes in content.
-- name: widget.content.allow-gtk-dark-theme
-  type: RelaxedAtomicBool
-  value: false
-  mirror: always
-
 # Whether native GTK context menus are enabled.
 # Disabled because at the very least there's missing custom icon support.
 - name: widget.gtk.native-context-menus

modules/libpref/init/all.js

@@ -3243,7 +3243,6 @@ pref("network.tcp.keepalive.idle_time", 600); // seconds; 10 mins
 pref("network.psl.onUpdate_notify", false);
 
 #ifdef MOZ_WIDGET_GTK
-  pref("widget.content.gtk-theme-override", "");
   pref("widget.disable-workspace-management", false);
   pref("widget.titlebar-x11-use-shape-mask", false);
 #endif

toolkit/components/telemetry/app/TelemetryEnvironment.sys.mjs

@@ -363,8 +363,6 @@ const DEFAULT_ENVIRONMENT_PREFS = new Map([
   ["signon.rememberSignons", { what: RECORD_PREF_VALUE }],
   ["signon.firefoxRelay.feature", { what: RECORD_PREF_VALUE }],
   ["toolkit.telemetry.pioneerId", { what: RECORD_PREF_STATE }],
-  ["widget.content.allow-gtk-dark-theme", { what: RECORD_DEFAULTPREF_VALUE }],
-  ["widget.content.gtk-theme-override", { what: RECORD_PREF_STATE }],
   [
     "widget.content.gtk-high-contrast.enabled",
     { what: RECORD_DEFAULTPREF_VALUE },

widget/LookAndFeelTypes.ipdlh

@@ -48,21 +48,11 @@ struct LookAndFeelTables {
     bool passwordEcho;
 };
 
-struct LookAndFeelTheme {
-#ifdef MOZ_WIDGET_GTK
-    nsCString themeName;
-    bool preferDarkTheme;
-#endif
-};
-
 /**
  * Stores the entirety of a LookAndFeel's data.
  */
 struct FullLookAndFeel {
     LookAndFeelTables tables;
-#ifdef MOZ_WIDGET_GTK
-    LookAndFeelTheme theme;
-#endif
 };
 
 } // namespace widget

widget/RemoteLookAndFeel.cpp

@@ -14,7 +14,6 @@
 #include "mozilla/Result.h"
 #include "mozilla/ResultExtensions.h"
 #include "mozilla/StaticPrefs_widget.h"
-#include "nsLookAndFeel.h"
 #include "nsXULAppAPI.h"
 
 #include <limits>
@@ -35,14 +34,6 @@ RemoteLookAndFeel::RemoteLookAndFeel(FullLookAndFeel&& aData)
     : mTables(std::move(aData.tables())) {
   MOZ_ASSERT(XRE_IsContentProcess(),
              "Only content processes should be using a RemoteLookAndFeel");
-
-#ifdef MOZ_WIDGET_GTK
-  if (!StaticPrefs::widget_non_native_theme_enabled()) {
-    // Configure the theme in this content process with the Gtk theme that was
-    // chosen by WithThemeConfiguredForContent in the parent process.
-    nsLookAndFeel::ConfigureTheme(aData.theme());
-  }
-#endif
 }
 
 RemoteLookAndFeel::~RemoteLookAndFeel() = default;
@@ -52,14 +43,6 @@ void RemoteLookAndFeel::SetDataImpl(FullLookAndFeel&& aData) {
              "Only content processes should be using a RemoteLookAndFeel");
   MOZ_ASSERT(NS_IsMainThread());
   mTables = std::move(aData.tables());
-
-#ifdef MOZ_WIDGET_GTK
-  if (!StaticPrefs::widget_non_native_theme_enabled()) {
-    // Configure the theme in this content process with the Gtk theme that was
-    // chosen by WithThemeConfiguredForContent in the parent process.
-    nsLookAndFeel::ConfigureTheme(aData.theme());
-  }
-#endif
 }
 
 namespace {
@@ -233,10 +216,6 @@ const FullLookAndFeel* RemoteLookAndFeel::ExtractData() {
   FullLookAndFeel* lf = new FullLookAndFeel{};
   nsXPLookAndFeel* impl = nsXPLookAndFeel::GetInstance();
 
-#ifdef MOZ_WIDGET_GTK
-  impl->GetGtkContentTheme(lf->theme());
-#endif
-
   lf->tables().passwordChar() = impl->GetPasswordCharacterImpl();
   lf->tables().passwordEcho() = impl->GetEchoPasswordImpl();
 

widget/gtk/nsLookAndFeel.cpp

@@ -1188,14 +1188,6 @@ static bool GetThemeIsDark() {
          RelativeLuminanceUtils::Compute(GDK_RGBA_TO_NS_RGBA(fg));
 }
 
-void nsLookAndFeel::ConfigureTheme(const LookAndFeelTheme& aTheme) {
-  MOZ_ASSERT(XRE_IsContentProcess());
-  GtkSettings* settings = gtk_settings_get_default();
-  g_object_set(settings, "gtk-theme-name", aTheme.themeName().get(),
-               "gtk-application-prefer-dark-theme",
-               aTheme.preferDarkTheme() ? TRUE : FALSE, nullptr);
-}
-
 void nsLookAndFeel::RestoreSystemTheme() {
   LOGLNF("RestoreSystemTheme(%s, %d, %d)\n", mSystemTheme.mName.get(),
          mSystemTheme.mPreferDarkTheme, mSystemThemeOverridden);
@@ -1553,19 +1545,6 @@ void nsLookAndFeel::ConfigureFinalEffectiveTheme() {
   }
 }
 
-void nsLookAndFeel::GetGtkContentTheme(LookAndFeelTheme& aTheme) {
-  if (NS_SUCCEEDED(Preferences::GetCString("widget.content.gtk-theme-override",
-                                           aTheme.themeName()))) {
-    return;
-  }
-
-  auto& theme = StaticPrefs::widget_content_allow_gtk_dark_theme()
-                    ? mSystemTheme
-                    : LightTheme();
-  aTheme.preferDarkTheme() = theme.mPreferDarkTheme;
-  aTheme.themeName() = theme.mName;
-}
-
 static nscolor GetBackgroundColor(
     GtkStyleContext* aStyle, nscolor aForForegroundColor,
     GtkStateFlags aState = GTK_STATE_FLAG_NORMAL,

widget/gtk/nsLookAndFeel.h

@@ -35,11 +35,8 @@ class nsLookAndFeel final : public nsXPLookAndFeel {
 
   bool GetDefaultDrawInTitlebar() override;
 
-  void GetGtkContentTheme(LookAndFeelTheme&) override;
   void GetThemeInfo(nsACString&) override;
 
-  static void ConfigureTheme(const LookAndFeelTheme& aTheme);
-
   static const nscolor kBlack = NS_RGB(0, 0, 0);
   static const nscolor kWhite = NS_RGB(255, 255, 255);
   void OnColorSchemeSettingChanged();

widget/moz.build

@@ -374,11 +374,8 @@ else:
     ]
 
 IPDL_SOURCES += [
-    "PClipboardWriteRequest.ipdl",
-]
-
-PREPROCESSED_IPDL_SOURCES += [
     "LookAndFeelTypes.ipdlh",
+    "PClipboardWriteRequest.ipdl",
 ]
 
 LOCAL_INCLUDES += [

widget/nsXPLookAndFeel.h

@@ -17,7 +17,6 @@ class nsXPLookAndFeel : public mozilla::LookAndFeel {
  public:
   using FullLookAndFeel = mozilla::widget::FullLookAndFeel;
   using LookAndFeelFont = mozilla::widget::LookAndFeelFont;
-  using LookAndFeelTheme = mozilla::widget::LookAndFeelTheme;
 
   virtual ~nsXPLookAndFeel();
 
@@ -67,7 +66,6 @@ class nsXPLookAndFeel : public mozilla::LookAndFeel {
 
   virtual void NativeInit() = 0;
 
-  virtual void GetGtkContentTheme(LookAndFeelTheme&) {}
   virtual void GetThemeInfo(nsACString&) {}
 
  protected: