test: make trace-viewer tests e2e

[Skn0tt]

As per #39121 (comment).

[github-actions]

Test results for "tests 1"

11 failed
❌ [firefox-library] › library/firefox/launcher.spec.ts:49 › should support custom firefox policies @firefox-ubuntu-22.04-node20
❌ [firefox-library] › library/trace-viewer.spec.ts:553 › should show snapshot URL and copy button @firefox-ubuntu-22.04-node20
❌ [firefox-library] › library/trace-viewer.spec.ts:770 › should restore scroll positions @firefox-ubuntu-22.04-node20
❌ [webkit-library] › library/trace-viewer.spec.ts:553 › should show snapshot URL and copy button @webkit-ubuntu-22.04-node20
❌ [webkit-library] › library/trace-viewer.spec.ts:896 › should handle src=blob @webkit-ubuntu-22.04-node20
❌ [webkit-library] › library/trace-viewer.spec.ts:1639 › should not leak recorders @webkit-ubuntu-22.04-node20
❌ [webkit-library] › library/trace-viewer.spec.ts:1807 › should show a modal dialog @webkit-ubuntu-22.04-node20
❌ [webkit-library] › library/trace-viewer.spec.ts:2163 › should respect CSSOM changes @webkit-ubuntu-22.04-node20
❌ [playwright-test] › expect.spec.ts:582 › should log scale the time @macos-latest-node20
❌ [playwright-test] › expect.spec.ts:642 › should only highlight unmatched regex in diff message for toHaveText with array @macos-latest-node20
❌ [playwright-test] › playwright.spec.ts:181 › should respect context options in various contexts @macos-latest-node20

6 flaky

⚠️ [chromium-library] › library/popup.spec.ts:258 › should not throw when click closes popup `@chromium-ubuntu-22.04-node22`
⚠️ [firefox-library] › library/inspector/cli-codegen-1.spec.ts:1082 › cli codegen › should not throw csp directive violation errors `@firefox-ubuntu-22.04-node20`
⚠️ [firefox-library] › library/inspector/cli-codegen-3.spec.ts:226 › cli codegen › should generate frame locators (4) `@firefox-ubuntu-22.04-node20`
⚠️ [firefox-library] › library/trace-viewer.spec.ts:1639 › should not leak recorders `@firefox-ubuntu-22.04-node20`
⚠️ [webkit-page] › page/page-event-console.spec.ts:250 › should have timestamp in consoleMessages `@webkit-ubuntu-22.04-node20`
⚠️ [playwright-test] › ui-mode-trace.spec.ts:700 › should indicate current test status `@windows-latest-node20`

38424 passed, 843 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

3 failed
❌ [chromium] › mcp/cli-help.spec.ts:24 › prints command help @mcp-macos-15
❌ [chromium] › mcp/cli-route.spec.ts:19 › route-list shows no routes when empty @mcp-macos-15
❌ [chromium] › mcp/launch.spec.ts:21 › test reopen browser @mcp-macos-15

4685 passed, 135 skipped

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Merge workflow run.