move format bar to own component

res/css/views/rooms/_MessageComposerFormatBar.scss

@@ -0,0 +1,81 @@
+/*
+Copyright 2019 New Vector Ltd
+Copyright 2019 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_MessageComposerFormatBar {
+    display: none;
+    width: calc(26px * 5);
+    height: 24px;
+    position: absolute;
+    cursor: pointer;
+    border-radius: 4px;
+    background-color: $message-action-bar-bg-color;
+    user-select: none;
+
+    &.mx_MessageComposerFormatBar_shown {
+        display: block;
+    }
+
+    > * {
+        white-space: nowrap;
+        display: inline-block;
+        position: relative;
+        border: 1px solid $message-action-bar-border-color;
+        margin-left: -1px;
+
+        &:hover {
+            border-color: $message-action-bar-hover-border-color;
+        }
+    }
+
+    .mx_MessageComposerFormatBar_button {
+        width: 27px;
+        height: 24px;
+        box-sizing: border-box;
+    }
+
+    .mx_MessageComposerFormatBar_button::after {
+        content: '';
+        position: absolute;
+        top: 0;
+        left: 0;
+        height: 100%;
+        width: 100%;
+        mask-repeat: no-repeat;
+        mask-position: center;
+        background-color: $message-action-bar-fg-color;
+    }
+
+    .mx_MessageComposerFormatBar_buttonIconBold::after {
+        mask-image: url('$(res)/img/format/bold.svg');
+    }
+
+    .mx_MessageComposerFormatBar_buttonIconItalic::after {
+        mask-image: url('$(res)/img/format/italics.svg');
+    }
+
+    .mx_MessageComposerFormatBar_buttonIconStrikethrough::after {
+        mask-image: url('$(res)/img/format/strikethrough.svg');
+    }
+
+    .mx_MessageComposerFormatBar_buttonIconQuote::after {
+        mask-image: url('$(res)/img/format/quote.svg');
+    }
+
+    .mx_MessageComposerFormatBar_buttonIconCode::after {
+        mask-image: url('$(res)/img/format/code.svg');
+    }
+}