Open new windows with a default size and position (#9204)

This PR changes GPUI to open windows with a default size and location,
and to otherwise inherit from their spawning window.

Note: The linux build now crashes on startup.

Release Notes:

- N/A

---------

Co-authored-by: Nathan <nathan@zed.dev>
Co-authored-by: Ezekiel Warren <zaucy@users.noreply.github.com>

crates/storybook/src/storybook.rs

@@ -7,8 +7,7 @@ mod story_selector;
 use clap::Parser;
 use dialoguer::FuzzySelect;
 use gpui::{
-    div, px, size, AnyView, AppContext, Bounds, Render, ViewContext, VisualContext, WindowBounds,
-    WindowOptions,
+    div, px, size, AnyView, AppContext, Bounds, Render, ViewContext, VisualContext, WindowOptions,
 };
 use log::LevelFilter;
 use settings::{default_settings, KeymapFile, Settings, SettingsStore};
@@ -85,12 +84,11 @@ fn main() {
         load_storybook_keymap(cx);
         cx.set_menus(app_menus());
 
+        let size = size(px(1500.), px(780.));
+        let bounds = Bounds::centered(size, cx);
         let _window = cx.open_window(
             WindowOptions {
-                bounds: WindowBounds::Fixed(Bounds {
-                    origin: Default::default(),
-                    size: size(px(1500.), px(780.)).into(),
-                }),
+                bounds: Some(bounds),
                 ..Default::default()
             },
             move |cx| {