Disable message box between send request and final send begin

Because we do a number of async checks before allowing the real send to
begin, on a slow matchine or when doing a lot of work (like receiving a
lot of messages) there can be a noticeable delay between hitting Enter
and the clearing of the text in the message box. In fact, newly-typed
text can be added to the previous message if the delay is long enough.

This prevents any interaction with the message box until the send has
either been prevented or has started.

FREEBIE

js/views/conversation_view.js

@@ -545,6 +545,7 @@
         },
 
         focusMessageField: function() {
+            this.$messageField.prop('disabled', false);
             this.$messageField.focus();
         },
 
@@ -857,6 +858,9 @@
         },
 
         checkUnverifiedSendMessage: function(e, options) {
+            e.preventDefault();
+            this.$messageField.prop('disabled', true);
+
             options = options || {};
             _.defaults(options, {force: false});
 
@@ -876,11 +880,12 @@
 
                 this.showSendConfirmationDialog(e, contacts);
             }.bind(this)).catch(function(error) {
+                this.focusMessageField();
                 console.log(
                     'checkUnverifiedSendMessage error:',
                     error && error.stack ? error.stack : error
                 );
-            });
+            }.bind(this));
         },
 
         checkUntrustedSendMessage: function(e, options) {
@@ -900,11 +905,12 @@
 
                 this.showSendConfirmationDialog(e, contacts);
             }.bind(this)).catch(function(error) {
+                this.focusMessageField();
                 console.log(
                     'checkUntrustedSendMessage error:',
                     error && error.stack ? error.stack : error
                 );
-            });
+            }.bind(this));
         },
 
         sendMessage: function(e) {
@@ -924,22 +930,24 @@
             if (toast) {
                 toast.$el.insertAfter(this.$el);
                 toast.render();
+                this.focusMessageField();
                 return;
             }
-            e.preventDefault();
+
             var input = this.$messageField;
             var message = this.replace_colons(input.val()).trim();
-            var convo = this.model;
-
-            this.focusMessageField();
 
             if (message.length > 0 || this.fileInput.hasFiles()) {
                 this.fileInput.getFiles().then(function(attachments) {
-                    convo.sendMessage(message, attachments);
-                });
-                input.val("");
-                this.forceUpdateMessageFieldSize(e);
-                this.fileInput.deleteFiles();
+                    this.model.sendMessage(message, attachments);
+                    input.val("");
+                    this.focusMessageField();
+                    this.forceUpdateMessageFieldSize(e);
+                    this.fileInput.deleteFiles();
+                }.bind(this)).catch(function() {
+                    console.log('Error pulling attached files before send');
+                    this.focusMessageField();
+                }.bind(this));
             }
         },