add message length warning for android clients

_locales/en/messages.json

@@ -351,6 +351,10 @@
         "message": "This version of Signal Desktop has expired. Please upgrade to the latest version to continue messaging.",
         "description": "Warning notification that this version of the app has expired"
     },
+    "androidMessageLengthWarning": {
+        "message": "Android clients will only receive the first 2000 characters of this message.",
+        "description": "Warning that long messages could not get received completely by Android clients."
+    },
     "upgrade": {
         "message": "Upgrade",
         "description": "Label text for button to upgrade the app to the latest version"

background.html

@@ -130,7 +130,9 @@ <h3>{{ welcomeToSignal }}</h3>
                 <div class='capture-audio'>
                     <button class='microphone'></button>
                 </div>
-
+                <div class='android-length-warning'>
+                    {{ android-length-warning }}
+                </div>
               </div>
           </form>
       </div>

js/views/conversation_view.js

@@ -78,6 +78,7 @@
                 'destroy'         : i18n('deleteMessages'),
                 'send-message'    : i18n('sendMessage'),
                 'disappearing-messages': i18n('disappearingMessages'),
+                'android-length-warning': i18n('androidMessageLengthWarning'),
                 timer_options     : Whisper.ExpirationTimerOptions.models
             };
         },
@@ -180,6 +181,13 @@
                 this.$('.capture-audio').show();
             }
         },
+        toggleLenghtWarning: function() {
+            if (this.$('.send-message').val().length > 2000 || this.fileInput.hasFiles()) {
+                this.$('.android-length-warning').show();
+            } else {
+                this.$('.android-length-warning').hide();
+            }
+        },
         captureAudio: function(e) {
             e.preventDefault();
             var view = new Whisper.RecorderView().render();
@@ -630,6 +638,7 @@
                 return this.$('.bottom-bar form').submit();
             }
             this.toggleMicrophone();
+            this.toggleLenghtWarning();
 
             this.view.measureScrollPosition();
             window.autosize(this.$messageField);

stylesheets/_conversation.scss

@@ -625,6 +625,10 @@ li.entry .error-icon-container {
     float: right;
     height: 36px;
   }
+  .android-length-warning {
+    padding: 10px;
+    max-width:150px;
+  }
 
 }