optimize re-rendering a conversation for a single outgoing message

Rather than rendering the conversation from scratch, look for
the special case of a single new message from the user that is
the last message, and just append the message HTML at the end of
the existing conversation.

To avoid stacking the new header on top of the previously last
message, do not notify ConversationContainer of dataset change
in this process. (An adapter dataset change means the container
will toss out all overlay views and immediately render given
the current spacers and adapter items. Do not want.)

The overlays for the new message will be drawn later when JS
notifies of a geometry change.

Bug: 7378693
Change-Id: Ifd2d3da8c57f685bbeae18f3d42c60821a97368c

1 files changed, 9 insertions, 0 deletions

diff --git a/assets/script.js b/assets/script.js
index 5ced9dd11..eafeba336 100644
--- a/assets/script.js
+++ b/assets/script.js
@@ -426,6 +426,15 @@ function replaceMessageBodies(messageIds) {
     }
 }
 
+// handle the special case of adding a single new message at the end of a conversation
+function appendMessageHtml() {
+    var msg = document.createElement("div");
+    msg.innerHTML = window.mail.getTempMessageBodies();
+    msg = msg.children[0];  // toss the outer div, it was just to render innerHTML into
+    document.body.appendChild(msg);
+    processQuotedText(msg, true /* showElided */);
+}
+
 // END Java->JavaScript handlers
 
 // Do this first to ensure that the readiness signal comes through,