Switch to the sha2 crate for SRI digests.

[fabricedesre]

This removes one (simple) use of OpenSSL

The update of content-security-policy ensures that we don't add a duplicate sha2 crate.

---

• ./mach build -d does not report any errors
• ./mach test-tidy does not report any errors
• These changes fix #___ (GitHub issue number if applicable)

• There are tests for these changes OR
• These changes do not require tests because it's a refactoring, no behavior change expected.

[jdm]

@bors-servo r+
Nice!

[bors-servo]

📌 Commit fec4c58 has been approved by jdm

[bors-servo]

⌛ Testing commit fec4c58 with merge 8ba9f18...

[github-actions]

Results from try job (#4268849638):

Flaky unexpected result (12)

• OK /_mozilla/mozilla/task_queue_throttling.any.html (#22519)
  • FAIL [expected PASS] subtest: Throttling the performance timeline task queue.
• TIMEOUT [expected OK] /_webgl/conformance/uniforms/out-of-bounds-uniform-array-access.html (#26225)
  • NOTRUN [expected PASS] subtest: Overall test
• OK /css/css-flexbox/text-as-flexitem-size-001.html (#28726)
  • FAIL [expected PASS] subtest: .flexbox > div 1
  • FAIL [expected PASS] subtest: .flexbox > div 2
  • FAIL [expected PASS] subtest: .flexbox > div 5
  • FAIL [expected PASS] subtest: .flexbox > div 8
  • FAIL [expected PASS] subtest: .flexbox > div 11
• OK /css/cssom-view/CaretPosition-001.html (#21338)
  • FAIL [expected PASS] subtest: Element at (400, 100)
• TIMEOUT [expected ERROR] /html/browsers/browsing-the-web/history-traversal/persisted-user-state-restoration/scroll-restoration-fragment-scrolling-cross-origin.html (#28541)
• OK /html/browsers/browsing-the-web/navigating-across-documents/navigate-to-unparseable-url.html (#29050)
  • PASS [expected FAIL] subtest: <a> tag navigate fails for unparseable URLs
• TIMEOUT [expected OK] /html/browsers/the-window-object/open-close/creating_browsing_context_test_01.html (#29046)
  • TIMEOUT [expected FAIL] subtest: first argument: absolute url
• OK /html/canvas/element/manual/image-smoothing/imagesmoothing.html (#28417)
  • FAIL [expected PASS] subtest: Test that imageSmoothingEnabled = false (nearest-neighbor interpolation) works with fillRect and createPattern().
• OK /html/semantics/links/links-created-by-a-and-area-elements/htmlanchorelement_noopener.html (#23205)
  • PASS [expected FAIL] subtest: Check that rel=noopener with target=_self does a normal load
• OK [expected TIMEOUT] /html/webappapis/scripting/processing-model-2/integration-with-the-javascript-job-queue/promise-job-entry-different-function-realm.html (#25805)
  • FAIL [expected TIMEOUT] subtest: Fulfillment handler on pending-then-fulfilled promise
  • FAIL [expected TIMEOUT] subtest: Rejection handler on pending-then-rejected promise
• OK [expected TIMEOUT] /webmessaging/with-ports/017.html (#24486)
  • PASS [expected TIMEOUT] subtest: origin of the script that invoked the method, about:blank
• TIMEOUT [expected OK] /webmessaging/with-ports/018.html (#24485)
  • TIMEOUT [expected PASS] subtest: origin of the script that invoked the method, javascript:

Stable unexpected results that are known to be intermittent (20)

• TIMEOUT /FileAPI/url/url-in-tags-revoke.window.html (#19978)
  • FAIL [expected TIMEOUT] subtest: Opening a blob URL in a new window immediately before revoking it works.
• OK /css/CSS2/floats/hit-test-floats-003.html (#25733)
  • PASS [expected FAIL] subtest: Miss float below something else
• OK /css/CSS2/linebox/inline-negative-margin-001.html (#23862)
  • PASS [expected FAIL] subtest: [data-expected-height] 1
  • PASS [expected FAIL] subtest: [data-expected-height] 2
  • FAIL [expected PASS] subtest: [data-expected-height] 4
• OK /css/css-transforms/transform-scale-hittest.html (#24667)
  • PASS [expected FAIL] subtest: Hit test within unscaled box
• OK /css/cssom-view/elementFromPoint-dynamic-anon-box.html (#22337)
  • PASS [expected FAIL] subtest: Link should be clickable after hiding a scrollbox with an anonymous table inside
• OK /css/cssom-view/elementFromPoint-float-in-relative.html (#27753)
  • PASS [expected FAIL] subtest: elementFromPoint-float-in-relative
• TIMEOUT /fetch/metadata/generated/css-images.sub.tentative.html (#29047)
  • PASS [expected TIMEOUT] subtest: background-image sec-fetch-site - HTTPS downgrade (header not sent)
• TIMEOUT /html/browsers/browsing-the-web/navigating-across-documents/javascript-url-no-beforeunload.window.html (#29055)
  • FAIL [expected TIMEOUT] subtest: Navigating an opened window with an iframe via location.href to a javascript: URL must not fire beforeunload on the iframe: undefined completion
  • PASS [expected NOTRUN] subtest: Navigating an iframe via location.href to a javascript: URL must not fire beforeunload: string completion
  • PASS [expected NOTRUN] subtest: Navigating an iframe via src="" to a javascript: URL after insertion must not fire beforeunload: string completion
  • TIMEOUT [expected NOTRUN] subtest: Navigating an opened window via location.href to a javascript: URL must not fire beforeunload: string completion
• TIMEOUT /html/browsers/browsing-the-web/navigating-across-documents/javascript-url-referrer.window.html (#29081)
  • FAIL [expected TIMEOUT] subtest: origin referrer policy used to create the starting page
  • TIMEOUT [expected NOTRUN] subtest: no-referrer referrer policy used to create the starting page
• OK /html/browsers/browsing-the-web/navigating-across-documents/navigation-unload-cross-origin.sub.window.html (#29056)
  • FAIL [expected PASS] subtest: Cross-origin navigation started from unload handler must be ignored
• CRASH [expected OK] /html/browsers/windows/embedded-opener-remove-frame.html (#23867)
• TIMEOUT /html/interaction/focus/the-autofocus-attribute/supported-elements.html (#24145)
  • FAIL [expected TIMEOUT] subtest: Element with tabindex should support autofocus
  • PASS [expected NOTRUN] subtest: Non-HTMLElement should not support autofocus
  • FAIL [expected NOTRUN] subtest: Host element with delegatesFocus should support autofocus
  • FAIL [expected NOTRUN] subtest: Host element with delegatesFocus including no focusable descendants should be skipped
  • TIMEOUT [expected NOTRUN] subtest: Area element should support autofocus
• OK [expected TIMEOUT] /html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-2.html (#22667)
  • FAIL [expected TIMEOUT] subtest: Check that popups from a sandboxed iframe escape the sandbox if
    allow-popups-to-escape-sandbox is used
• OK [expected TIMEOUT] /html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-3.html (#24057)
  • FAIL [expected TIMEOUT] subtest: Check that popups from a sandboxed iframe escape the sandbox if
    allow-popups-to-escape-sandbox is used
• OK [expected CRASH] /html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-1.html (#24066)
• OK [expected TIMEOUT] /html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-2.html (#22154)
  • FAIL [expected NOTRUN] subtest: Check that popups from a sandboxed iframe do not escape the sandbox
• OK /html/semantics/embedded-content/the-img-element/non-active-document.html (#21544)
  • FAIL [expected PASS] subtest: createHTMLDocument
  • FAIL [expected PASS] subtest: <template>
• OK /html/semantics/forms/form-submission-0/urlencoded2.window.html (#28687)
  • FAIL [expected PASS] subtest: application/x-www-form-urlencoded: 0x00 in filename (formdata event)
  • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: single quote in name (formdata event)
• TIMEOUT [expected OK] /html/webappapis/scripting/processing-model-2/unhandled-promise-rejections/promise-rejection-events.html (#26371)
  • TIMEOUT [expected FAIL] subtest: delayed handling: delaying handling rejected promise created from createImageBitmap will cause both events to fire
• CRASH [expected TIMEOUT] /webmessaging/broadcastchannel/cross-partition.https.tentative.html (#29058)

[bors-servo]

☀️ Test successful - checks-github
Approved by: jdm
Pushing 8ba9f18 to master...