Don't return html in the text field.

lib/pleroma/web/twitter_api/representers/activity_representer.ex

@@ -33,7 +33,7 @@ def to_map(%Activity{} = activity, %{user: user} = opts) do
       "user" => UserRepresenter.to_map(user, opts),
       "attentions" => [],
       "statusnet_html" => content,
-      "text" => content,
+      "text" => HtmlSanitizeEx.strip_tags(content),
       "is_local" => true,
       "is_post_verb" => true,
       "created_at" => published,

test/web/twitter_api/representers/activity_representer_test.exs

@@ -23,7 +23,8 @@ test "an activity" do
       }
     }
 
-    content = "Some content mentioning @shp"
+    content_html = "Some content mentioning <a href='shp'>@shp</shp>"
+    content = HtmlSanitizeEx.strip_tags(content_html)
     date = DateTime.utc_now() |> DateTime.to_iso8601
 
     activity = %Activity{
@@ -39,7 +40,7 @@ test "an activity" do
         "object" => %{
           "published" => date,
           "type" => "Note",
-          "content" => content,
+          "content" => content_html,
           "inReplyToStatusId" => 213123,
           "statusnetConversationId" => 4711,
           "attachment" => [
@@ -56,7 +57,7 @@ test "an activity" do
       "user" => UserRepresenter.to_map(user, %{for: follower}),
       "is_local" => true,
       "attentions" => [],
-      "statusnet_html" => content,
+      "statusnet_html" => content_html,
       "text" => content,
       "is_post_verb" => true,
       "created_at" => date,