FIX: Properly associate user_profiles background urls via upload id.

`Upload#url` is more likely and can change from time to time. When it
does changes, we don't want to have to look through multiple tables to
ensure that the URLs are all up to date. Instead, we simply associate
uploads properly to `UserProfile` so that it does not have to replicate
the URLs in the table.

app/assets/javascripts/discourse/components/user-card-contents.js.es6

@@ -131,7 +131,7 @@ export default Ember.Component.extend(
       }
     },
 
-    @observes("user.card_background")
+    @observes("user.card_background_upload_url")
     addBackground() {
       if (!this.get("allowBackgrounds")) {
         return;
@@ -142,7 +142,7 @@ export default Ember.Component.extend(
         return;
       }
 
-      const url = this.get("user.card_background");
+      const url = this.get("user.card_background_upload_url");
       const bg = Ember.isEmpty(url)
         ? ""
         : `url(${Discourse.getURLWithCDN(url)})`;

app/assets/javascripts/discourse/controllers/preferences/profile.js.es6

@@ -10,8 +10,8 @@ export default Ember.Controller.extend(PreferencesTabController, {
     "location",
     "custom_fields",
     "user_fields",
-    "profile_background",
-    "card_background",
+    "profile_background_upload_url",
+    "card_background_upload_url",
     "date_of_birth"
   ],
 

app/assets/javascripts/discourse/controllers/user.js.es6

@@ -21,8 +21,8 @@ export default Ember.Controller.extend(CanCheckEmails, {
     return !profileHidden && viewingSelf;
   },
 
-  @computed("model.profileBackground")
-  hasProfileBackground(background) {
+  @computed("model.profileBackgroundUrl")
+  hasProfileBackgroundUrl(background) {
     return !Ember.isEmpty(background.toString());
   },
 

app/assets/javascripts/discourse/models/user.js.es6

@@ -77,8 +77,8 @@ const User = RestModel.extend({
     return username;
   },
 
-  @computed("profile_background")
-  profileBackground(bgUrl) {
+  @computed("profile_background_upload_url")
+  profileBackgroundUrl(bgUrl) {
     if (
       Ember.isEmpty(bgUrl) ||
       !Discourse.SiteSettings.allow_profile_backgrounds
@@ -250,8 +250,8 @@ const User = RestModel.extend({
       "user_fields",
       "muted_usernames",
       "ignored_usernames",
-      "profile_background",
-      "card_background",
+      "profile_background_upload_url",
+      "card_background_upload_url",
       "muted_tags",
       "tracked_tags",
       "watched_tags",

app/assets/javascripts/discourse/templates/preferences/profile.hbs

@@ -32,7 +32,8 @@
   <div class="control-group pref-profile-bg">
     <label class="control-label">{{i18n 'user.change_profile_background.title'}}</label>
     <div class="controls">
-      {{image-uploader imageUrl=model.profile_background type="profile_background"}}
+      {{image-uploader imageUrl=model.profile_background_upload_url
+                       type="profile_background"}}
     </div>
     <div class='instructions'>
       {{i18n 'user.change_profile_background.instructions'}}
@@ -42,7 +43,8 @@
   <div class="control-group pref-profile-bg">
     <label class="control-label">{{i18n 'user.change_card_background.title'}}</label>
     <div class="controls">
-      {{image-uploader imageUrl=model.card_background type="card_background"}}
+      {{image-uploader imageUrl=model.card_background_upload_url
+                       type="card_background"}}
     </div>
     <div class='instructions'>
       {{i18n 'user.change_card_background.instructions'}}

app/assets/javascripts/discourse/templates/user.hbs

@@ -1,7 +1,7 @@
 <div class="container {{if viewingSelf 'viewing-self'}}">
   {{#d-section class="user-main"}}
 
-    <section class="{{if collapsedInfo 'collapsed-info'}} about {{if hasProfileBackground 'has-background' 'no-background'}}" >
+    <section class="{{if collapsedInfo 'collapsed-info'}} about {{if hasProfileBackgroundUrl 'has-background' 'no-background'}}" >
     {{#unless collapsedInfo}}
     {{#if showStaffCounters}}
       <div class='staff-counters'>
@@ -34,7 +34,7 @@
         {{/if}}
       </div>
     {{/if}}
-    <div class="user-profile-image" style={{model.profileBackground}}></div>
+    <div class="user-profile-image" style={{model.profileBackgroundUrl}}></div>
     {{/unless}}
 
       <div class='details'>