LibGfx+Userland: Make Gfx::SystemTheme propagate errors

This patch introduces error propagation to Gfx::SystemTheme to remove
instances of release_value_but_fixme_should_propagate_errors().

Userland applications that have been affected by this change have been
updated to utilise this propagation and as a result 4 such instances of
the aforementioned method have been removed.

1 files changed, 7 insertions, 4 deletions

diff --git a/Userland/Utilities/headless-browser.cpp b/Userland/Utilities/headless-browser.cpp
index c1aaa5c869..2e8d2df8a3 100644
--- a/Userland/Utilities/headless-browser.cpp
+++ b/Userland/Utilities/headless-browser.cpp
@@ -771,10 +771,13 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
 
     auto page_client = HeadlessBrowserPageClient::create();
 
-    if (!resources_folder.is_empty())
-        page_client->setup_palette(Gfx::load_system_theme(LexicalPath::join(resources_folder, "themes/Default.ini"sv).string()));
-    else
-        page_client->setup_palette(Gfx::load_system_theme("/res/themes/Default.ini"));
+    if (!resources_folder.is_empty()) {
+        auto system_theme = TRY(Gfx::load_system_theme(LexicalPath::join(resources_folder, "themes/Default.ini"sv).string()));
+        page_client->setup_palette(system_theme);
+    } else {
+        auto system_theme = TRY(Gfx::load_system_theme("/res/themes/Default.ini"));
+        page_client->setup_palette(system_theme);
+    }
 
     dbgln("Loading {}", url);
     page_client->load(AK::URL(url));