Bug 1735358 - [devtools] Switch back default theme from auto to light/dark r=nchevobbe

Depends on D128093

We will attempt to re-enable the auto theme by default in Bug 1735359

Differential Revision: https://phabricator.services.mozilla.com/D128239

devtools/client/framework/test/browser_toolbox_theme_registration.js

@@ -135,12 +135,12 @@ add_task(async function themeUnregistration() {
 
   is(
     gDevTools.getTheme(),
-    gDevTools.getAutoTheme(),
+    LIGHT_THEME_NAME,
     "getTheme returns the expected theme"
   );
   is(
     eventsRecorded.pop(),
-    gDevTools.getAutoTheme(),
+    LIGHT_THEME_NAME,
     "theme-changed fired with the expected theme"
   );
   ok(
@@ -151,10 +151,12 @@ add_task(async function themeUnregistration() {
   const doc = panelWin.frameElement.contentDocument;
   const themeBox = doc.getElementById("devtools-theme-box");
 
-  // The default theme must be selected now.
-  ok(
-    themeBox.querySelector(`#devtools-theme-box [value=auto]`).checked,
-    `auto theme must be selected`
+  // The default light theme must be selected now.
+  is(
+    themeBox.querySelector(`#devtools-theme-box [value=${LIGHT_THEME_NAME}]`)
+      .checked,
+    true,
+    `${LIGHT_THEME_NAME} theme must be selected`
   );
 
   gDevTools.off("theme-changed", onThemeChanged);

modules/libpref/init/all.js

@@ -4491,7 +4491,11 @@ pref("services.common.log.logger.tokenserverclient", "Debug");
 pref("devtools.jsonview.enabled", true);
 
 // Default theme ("auto", "dark" or "light").
-pref("devtools.theme", "auto", sticky);
+#ifdef MOZ_DEV_EDITION
+  pref("devtools.theme", "dark", sticky);
+#else
+  pref("devtools.theme", "light", sticky);
+#endif
 
 // Completely disable DevTools entry points, as well as all DevTools command
 // line arguments This should be merged with devtools.enabled, see Bug 1440675.