Add user interface frontend for editing messages.

The only known outstanding bug with this is that it doesn't properly
handle the updating of a message's highlighting/presence in a narrowed
view (e.g. in theory, a message should disappear if it is edited such
that its subject doesn't match your narrow or it no longer matches
your search).  I think I'll just open a trac ticket about that once
this is merged, since it's a little hairy to deal with and kinda a
marginal use case.

Also it's not pretty, but that should be easy to tweak once we get the
framework merged.

Conflicts:
	tools/jslint/check-all.js

(imported from commit 2d0e3a440bcd885546bd8e28aff97bf379649950)

zephyr/static/js/message_edit.js

@@ -0,0 +1,89 @@
+var message_edit = (function () {
+var exports = {};
+var currently_editing_messages = {};
+
+exports.save = function (row) {
+    var msg_list = current_msg_list;
+    var message = current_msg_list.get(rows.id(row));
+    var new_subject = row.find(".message_edit_subject").val();
+    var new_content = row.find(".message_edit_content").val();
+    var request = {message_id: message.id};
+    if (new_subject !== message.subject) {
+        request.subject = new_subject;
+    }
+    if (new_content !== message.raw_content) {
+        request.content = new_content;
+    }
+    if (request.subject === undefined &&
+        request.content === undefined) {
+        // If they didn't change anything, just cancel it.
+        return message_edit.cancel(row);
+    }
+    $.ajax({
+        type: 'POST',
+        url: '/json/update_message',
+        data: request,
+        dataType: 'json',
+        success: function (data) {
+            if (msg_list === current_msg_list) {
+                message_edit.cancel(row);
+            }
+        }
+    });
+    // The message will automatically get replaced when it arrives.
+};
+
+function edit_message (row, raw_content) {
+    var message = current_msg_list.get(rows.id(row));
+    var edit_row = row.find(".message_edit");
+    var form = $(templates.render('message_edit_form',
+                                  {is_stream: message.is_stream,
+                                   subject: message.subject,
+                                   content: raw_content}));
+
+    var edit_obj = {form: form, raw_content: raw_content};
+    current_msg_list.show_edit_message(row, edit_obj);
+
+    currently_editing_messages[message.id] = edit_obj;
+}
+
+exports.start = function (row) {
+    var message = current_msg_list.get(rows.id(row));
+    var msg_list = current_msg_list;
+    $.ajax({
+        type: 'POST',
+        url: '/json/fetch_raw_message',
+        data: {message_id: message.id},
+        dataType: 'json',
+        success: function (data) {
+            if (current_msg_list === msg_list) {
+                message.raw_content = data.raw_content;
+                edit_message(row, data.raw_content);
+            }
+        }
+    });
+};
+
+exports.cancel = function (row) {
+    var message = current_msg_list.get(rows.id(row));
+    delete currently_editing_messages[message.id];
+    current_msg_list.hide_edit_message(row);
+};
+
+exports.maybe_show_edit = function(row, id) {
+    if (currently_editing_messages[id] !== undefined){
+        current_msg_list.show_edit_message(row, currently_editing_messages[id]);
+    }
+};
+
+$(document).on('narrow_deactivated.zephyr', function (event) {
+    $.each(currently_editing_messages, function(idx, elem) {
+        if (current_msg_list.get(idx) !== undefined) {
+            var row = rows.get(idx, current_msg_list.table_name);
+            current_msg_list.show_edit_message(row, elem);
+        }
+    });
+});
+
+return exports;
+}());