Be case-insensitive about subjects when collapsing and narrowing.

(imported from commit 0baf20179c037c3eac82d8db20c6ec8062bb136a)

tools/jslint/check-all.js

@@ -47,7 +47,7 @@ var globals =
 
     // zephyr.js
     + ' message_array message_dict get_updates_params'
-    + ' clear_table add_to_table subject_dict'
+    + ' clear_table add_to_table subject_dict same_stream_and_subject'
     + ' keep_pointer_in_view move_pointer_at_page_top_and_bottom'
     + ' respond_to_message'
     + ' select_message select_message_by_id'

zephyr/static/js/narrow.js

@@ -107,9 +107,8 @@ exports.by_subject = function () {
         subject:     original.subject
     };
     do_narrow(bar, function (other) {
-        return (other.type === 'stream' &&
-                original.recipient_id === other.recipient_id &&
-                original.subject === other.subject);
+        return ((other.type === 'stream') &&
+                same_stream_and_subject(original, other));
     });
 };
 

zephyr/static/js/zephyr.js

@@ -199,6 +199,13 @@ function select_message(next_message, opts) {
     return true;
 }
 
+function same_stream_and_subject(a, b) {
+    // Streams and subjects are case-insensitive. Streams have
+    // already been forced to the canonical case.
+    return ((a.recipient_id === b.recipient_id) &&
+            (a.subject.toLowerCase() === b.subject.toLowerCase()));
+}
+
 function same_recipient(a, b) {
     if ((a === undefined) || (b === undefined))
         return false;
@@ -211,8 +218,7 @@ function same_recipient(a, b) {
     case 'personal':
         return a.reply_to === b.reply_to;
     case 'stream':
-        return (a.recipient_id === b.recipient_id) &&
-               (a.subject      === b.subject);
+        return same_stream_and_subject(a, b);
     }
 
     // should never get here