commit 25937b12aa3475c9e914d18fbfa5c0614777ac94
Author: Ben Rohlfs <brohlfs@google.com>
Date:   Tue Oct 6 15:12:53 2020 +0200

    Fix showing the CC section in the attention modify section
    
    The visibility of the CC section was just based on observing _ccs as a
    whole, but that is just a constant array, which will never change. So
    instead we introduce a new property `_attentionCcsCount`, which is
    updated when the attention set is re-calculated, which observes
    `_ccs.*`, not just `_ccs`.
    
    Change-Id: I1c7ba406b41a44873757c339a8a8a9595cc4c5e4

diff --git a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts
index a2a75d0..eeefe45 100644
--- a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts
+++ b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.ts
@@ -273,6 +273,9 @@ export class GrReplyDialog extends KeyboardShortcutMixin(
   @property({type: Array})
   _ccs: (AccountInfo | GroupInfo)[] = [];
 
+  @property({type: Number})
+  _attentionCcsCount = 0;
+
   @property({type: Object, observer: '_reviewerPendingConfirmationUpdated'})
   _ccPendingConfirmation: GroupObjectInput | null = null;
 
@@ -948,7 +951,7 @@ export class GrReplyDialog extends KeyboardShortcutMixin(
       AccountInfoInput[],
       AccountInfoInput[]
     >,
-    _?: PolymerDeepPropertyChange<AccountInfoInput[], AccountInfoInput[]>,
+    ccs?: PolymerDeepPropertyChange<AccountInfoInput[], AccountInfoInput[]>,
     change?: ChangeInfo,
     draftCommentThreads?: CommentThread[],
     includeComments?: boolean
@@ -957,6 +960,7 @@ export class GrReplyDialog extends KeyboardShortcutMixin(
       currentUser === undefined ||
       currentUser._account_id === undefined ||
       reviewers === undefined ||
+      ccs === undefined ||
       change === undefined ||
       draftCommentThreads === undefined ||
       includeComments === undefined
@@ -966,6 +970,7 @@ export class GrReplyDialog extends KeyboardShortcutMixin(
     // The draft comments are only relevant for the attention set as long as the
     // user actually plans to publish their drafts.
     draftCommentThreads = includeComments ? draftCommentThreads : [];
+    this._attentionCcsCount = removeServiceUsers(ccs.base).length;
     this._currentAttentionSet = new Set(
       Object.keys(change.attention_set || {}).map(
         id => parseInt(id) as AccountId
@@ -1124,10 +1129,6 @@ export class GrReplyDialog extends KeyboardShortcutMixin(
     return removeServiceUsers(accounts);
   }
 
-  _computeShowAttentionCcs(ccs: AccountInfo[]) {
-    return removeServiceUsers(ccs).length > 0;
-  }
-
   _computeUploader(change: ChangeInfo) {
     if (
       !change ||
diff --git a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog_html.ts b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog_html.ts
index f076981..2413c97 100644
--- a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog_html.ts
+++ b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog_html.ts
@@ -514,7 +514,7 @@ export const htmlTemplate = html`
             </template>
           </div>
         </div>
-        <template is="dom-if" if="[[_computeShowAttentionCcs(_ccs)]]">
+        <template is="dom-if" if="[[_attentionCcsCount]]">
           <div class="peopleList">
             <div class="peopleListLabel">CC</div>
             <div>