fix(chromium): handle empty url for initial empty page

[pavelfeldman]

Summary

• In r1651606 Chromium changed the URL reported for the initial empty document from ":" to "". Accept both when detecting the initial empty page.

[github-actions]

Test results for "MCP"

2 failed
❌ [firefox] › mcp/http.spec.ts:349 › client should receive list roots request @mcp-ubuntu-latest-firefox
❌ [firefox] › mcp/http.spec.ts:349 › client should receive list roots request @mcp-macos-latest-firefox

7381 passed, 1132 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 1"

3 failed
❌ [chromium-library] › library/browsercontext-add-init-script.spec.ts:28 › should work without navigation, after all bindings @chromium-ubuntu-22.04-arm-node20
❌ [chromium-library] › library/browsercontext-expose-function.spec.ts:77 › should be callable from-inside addInitScript @chromium-ubuntu-22.04-arm-node20
❌ [playwright-test] › basic.spec.ts:414 › should hint at async describe() callbacks when test() is called too late @ubuntu-latest-node20

5 flaky

⚠️ [chromium-library] › library/chromium/chromium.spec.ts:299 › should report intercepted service worker requests in HAR `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/video.spec.ts:717 › screencast › should work with video+trace `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/chromium/chromium.spec.ts:299 › should report intercepted service worker requests in HAR `@chromium-ubuntu-22.04-node20`
⚠️ [chromium-library] › library/video.spec.ts:717 › screencast › should work with video+trace `@chromium-ubuntu-22.04-node22`
⚠️ [firefox-page] › page/page-emulate-media.spec.ts:144 › should keep reduced motion and color emulation after reload `@firefox-ubuntu-22.04-node20`

49080 passed, 1156 skipped

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Merge workflow run.