Backport new version to p9 branch.

New release (93.0).
Security fixes:
2021-38496: Use-after-free in MessageTask
2021-38497: Validation message could have been overlaid on another origin
2021-38498: Use-after-free of nsLanguageAtomService object
2021-32810: Data race in crossbeam-deque
2021-38500: Memory safety bugs fixed in Firefox 93, Firefox ESR 78.15, and Firefox ESR 91.2
2021-38501: Memory safety bugs fixed in Firefox 93 and Firefox ESR 91.2
2021-38499: Memory safety bugs fixed in Firefox 93

New release (92.0.1).

New release (92.0).
Security fixes:
2021-29993: Handling custom intents could lead to crashes and UI spoofs
2021-38491: Mixed-Content-Blocking was unable to check opaque origins
2021-38492: Navigating to `mk:` URL scheme could load Internet Explorer
2021-38493: Memory safety bugs fixed in Firefox 92, Firefox ESR 78.14 and Firefox ESR 91.1
2021-38494: Memory safety bugs fixed in Firefox 92

Rebuild with llvm12.0.

New release (91.0.2).

New release (91.0.1).
Security fixes:
2021-29991: Header Splitting possible with HTTP/3 Responses

New release (91.0).
Security fixes:
2021-29986: Race condition when resolving DNS names could have led to memory corruption
2021-29981: Live range splitting could have led to conflicting assignments in the JIT
2021-29988: Memory corruption as a result of incorrect style treatment
2021-29983: Firefox for Android could get stuck in fullscreen mode
2021-29984: Incorrect instruction reordering during JIT optimization
2021-29980: Uninitialized memory in a canvas object could have led to memory corruption
2021-29987: Users could have been tricked into accepting unwanted permissions on Linux
2021-29985: Use-after-free media channels
2021-29982: Single bit data leak due to incorrect JIT optimization and type confusion
2021-29989: Memory safety bugs fixed in Firefox 91 and Firefox ESR 78.13
2021-29990: Memory safety bugs fixed in Firefox 91

New release (90.0.2).

New release (90.0.1).

New release (90.0).
Move rpm-build-firefox from firefox to separate package.
Security fixes:
2021-29970: Use-after-free in accessibility features of a document
2021-29971: Granted permissions only compared host; omitting scheme and port on Android
2021-30547: Out of bounds write in ANGLE
2021-29972: Use of out-of-date library included use-after-free vulnerability
2021-29973: Password autofill on HTTP websites was enabled without user interaction on Android
2021-29974: HSTS errors could be overridden when network partitioning was enabled
2021-29975: Text message could be overlaid on top of another website
2021-29976: Memory safety bugs fixed in Firefox 90 and Firefox ESR 78.12
2021-29977: Memory safety bugs fixed in Firefox 90

Enable searching system- and account-global directories for extensions (ALT#40364).

New release (89.0.2).

New release (89.0.1).
Security fixes:
2021-29968: Out of bounds read when drawing text characters onto a Canvas

New release (89.0).
Security fixes:
2021-29965: Password Manager on Firefox for Android susceptible to domain spoofing
2021-29960: Filenames printed from private browsing mode incorrectly retained in preferences
2021-29961: Firefox UI spoof using `<select>` elements and CSS scaling
2021-29963: Shared cookies for search suggestions in private browsing mode
2021-29964: Out of bounds-read when parsing a `WM_COPYDATA` message
2021-29959: Devices could be re-enabled without additional permission prompt
2021-29962: No rate-limiting for popups on Firefox for Android
2021-29967: Memory safety bugs fixed in Firefox 89 and Firefox ESR 78.11
2021-29966: Memory safety bugs fixed in Firefox 89

New release (88.0.1).
Security fixes:
2021-29953: Universal Cross-Site Scripting
2021-29952: Race condition in Web Render Components