Support for login + E2EE set up with QR (#9403)

* Support for login + E2EE set up with QR

* Whitespace

* Padding

* Refactor of fetch

* Whitespace

* CSS whitespace

* Add link to MSC3906

* Handle incorrect typing in MatrixClientPeg.get()

* Use unstable class name

* fix: use unstable class name

* Use default fetch client instead

* Update to revised function name

* Refactor device manager panel and make it work with new sessions manager

* Lint fix

* Add missing interstitials and update wording

* Linting

* i18n

* Lint

* Use sensible sdk config name for fallback server

* Improve error handling for QR code generation

* Refactor feature availability logic

* Hide device manager panel if no options available

* Put sign in with QR behind lab setting

* Reduce scope of PR to just showing code on existing device

* i18n updates

* Handle null features

* Testing for LoginWithQRSection

* Refactor to handle UIA

* Imports

* Reduce diff complexity

* Remove unnecessary change

* Remove unused styles

* Support UIA

* Tidy up

* i18n

* Remove additional unused parts of flow

* Add extra instruction when showing QR code

* Add getVersions to server mocks

* Use proper colours for theme support

* Test cases

* Lint

* Remove obsolete snapshot

* Don't override error if already set

* Remove unused var

* Update src/components/views/settings/devices/LoginWithQRSection.tsx

Co-authored-by: Travis Ralston <travisr@matrix.org>

* Update src/components/views/auth/LoginWithQR.tsx

Co-authored-by: Travis Ralston <travisr@matrix.org>

* Update src/components/views/auth/LoginWithQR.tsx

Co-authored-by: Travis Ralston <travisr@matrix.org>

* Update src/components/views/auth/LoginWithQR.tsx

Co-authored-by: Travis Ralston <travisr@matrix.org>

* Update src/components/views/auth/LoginWithQR.tsx

Co-authored-by: Travis Ralston <travisr@matrix.org>

* Update src/components/views/auth/LoginWithQR.tsx

Co-authored-by: Travis Ralston <travisr@matrix.org>

* Update res/css/views/auth/_LoginWithQR.pcss

Co-authored-by: Kerry <kerrya@element.io>

* Use spacing variables

* Remove debug

* Style + docs

* preventDefault

* Names of tests

* Fixes for js-sdk refactor

* Update snapshots to match test names

* Refactor labs config to make deployment simpler

* i18n

* Unused imports

* Typo

* Stateless component

* Whitespace

* Use context not MatrixClientPeg

* Add missing context

* Type updates to match js-sdk

* Wrap click handlers in useCallback

* Update src/components/views/settings/DevicesPanel.tsx

Co-authored-by: Travis Ralston <travisr@matrix.org>

* Wait for DOM update instead of timeout

* Add missing snapshot update from last commit

* Remove void keyword in favour of then() clauses

* test main paths in LoginWithQR

Co-authored-by: Travis Ralston <travisr@matrix.org>
Co-authored-by: Kerry <kerrya@element.io>

res/css/_components.pcss

@@ -96,6 +96,7 @@
 @import "./views/auth/_CountryDropdown.pcss";
 @import "./views/auth/_InteractiveAuthEntryComponents.pcss";
 @import "./views/auth/_LanguageSelector.pcss";
+@import "./views/auth/_LoginWithQR.pcss";
 @import "./views/auth/_PassphraseField.pcss";
 @import "./views/auth/_Welcome.pcss";
 @import "./views/avatars/_BaseAvatar.pcss";

res/css/views/auth/_LoginWithQR.pcss

@@ -0,0 +1,171 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+.mx_LoginWithQRSection .mx_AccessibleButton {
+    margin-right: $spacing-12;
+}
+
+.mx_AuthPage .mx_LoginWithQR {
+    .mx_AccessibleButton {
+        display: block !important;
+    }
+
+    .mx_AccessibleButton + .mx_AccessibleButton {
+        margin-top: $spacing-8;
+    }
+
+    .mx_LoginWithQR_separator {
+        display: flex;
+        align-items: center;
+        text-align: center;
+
+        &::before, &::after {
+            content: '';
+            flex: 1;
+            border-bottom: 1px solid $quinary-content;
+        }
+
+        &:not(:empty) {
+            &::before {
+                margin-right: 1em;
+            }
+            &::after {
+                margin-left: 1em;
+            }
+        }
+    }
+
+    font-size: $font-15px;
+}
+
+.mx_UserSettingsDialog .mx_LoginWithQR {
+    .mx_AccessibleButton + .mx_AccessibleButton {
+        margin-left: $spacing-12;
+    }
+
+    font-size: $font-14px;
+
+    h1 {
+        font-size: $font-24px;
+        margin-bottom: 0;
+    }
+
+    li {
+        line-height: 1.8;
+    }
+
+    .mx_QRCode {
+        padding: $spacing-12 $spacing-40;
+        margin: $spacing-28 0;
+    }
+
+    .mx_LoginWithQR_buttons {
+        text-align: center;
+    }
+
+    .mx_LoginWithQR_qrWrapper {
+        display: flex;
+    }
+}
+
+.mx_LoginWithQR {
+    min-height: 350px;
+    display: flex;
+    flex-direction: column;
+
+    .mx_LoginWithQR_centreTitle {
+        h1 {
+            text-align: centre;
+        }
+    }
+
+    h1 > svg {
+        &.normal {
+            color: $secondary-content;
+        }
+        &.error {
+            color: $alert;
+        }
+        &.success {
+            color: $accent;
+        }
+        height: 1.3em;
+        margin-right: $spacing-8;
+        vertical-align: middle;
+    }
+
+    .mx_LoginWithQR_confirmationDigits {
+        text-align: center;
+        margin: $spacing-48 auto;
+        font-weight: 600;
+        font-size: $font-24px;
+        color: $primary-content;
+    }
+
+    .mx_LoginWithQR_confirmationAlert {
+        border: 1px solid $quaternary-content;
+        border-radius: $spacing-8;
+        padding: $spacing-8;
+        line-height: 1.5em;
+        display: flex;
+
+        svg {
+            height: 30px;
+        }
+    }
+
+    .mx_LoginWithQR_separator {
+        margin: 1em 0;
+    }
+
+    ol {
+        list-style-position: inside;
+        padding-inline-start: 0;
+
+        li::marker {
+            color: $accent;
+        }
+    }
+
+    .mx_LoginWithQR_BackButton {
+        height: $spacing-12;
+        margin-bottom: $spacing-24;
+        svg {
+            height: 100%;
+        }
+    }
+
+    .mx_LoginWithQR_main {
+        display: flex;
+        flex-direction: column;
+        flex-grow: 1;
+    }
+
+    .mx_QRCode {
+        border: 1px solid $quinary-content;
+        border-radius: $spacing-8;
+        display: flex;
+        justify-content: center;
+    }
+
+    .mx_LoginWithQR_spinner {
+        flex-grow: 1;
+        display: flex;
+        justify-content: center;
+        align-items: center;
+        height: 100%;
+    }
+}