Served with isolation headers; start-screen capability notices; tests on the real GPU (t88 phase 1)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tools/test_perf.py

@@ -6,8 +6,8 @@ import math
 import copy
 from urllib.request import urlopen
 
-from perf import ROOT, GPU_ARGS, quantiles, measurements, report
-from server import isolated_server
+from perf import ROOT, quantiles, measurements, report
+from browser import launch, consume_gpu_option
 from use_venv import ensure_playwright
 
 
@@ -28,14 +28,12 @@ def main():
     assert '/factory/sim/total_ms: +20.0% REGRESSION' in out.getvalue()
     assert 'n/a (baseline zero)' in out.getvalue()
     ensure_playwright()
-    from playwright.sync_api import sync_playwright
-    with isolated_server() as url, sync_playwright() as p:
+    consume_gpu_option()
+    with launch() as (browser, pg, url):
         with urlopen(url) as response:
             assert response.headers['Cross-Origin-Opener-Policy'] == 'same-origin'
             assert response.headers['Cross-Origin-Embedder-Policy'] == 'require-corp'
             response.read()
-        browser = p.chromium.launch(args=GPU_ARGS)
-        pg = browser.new_page(viewport={'width': 1280, 'height': 760})
         errors = []
         pg.on('pageerror', lambda e: errors.append(str(e)))
         pg.add_init_script('window.requestAnimationFrame = () => 0;')