[geary/wip/743676-cid] Addt'l documentation

[Jim Nelson <jnelson src gnome org>]

commit 9e53d3404e32d497c48b71d07ea9f7968f2037e5
Author: Jim Nelson <jim yorba org>
Date:   Thu Feb 12 17:33:42 2015 -0800

    Addt'l documentation

 .../conversation-viewer/conversation-viewer.vala   |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/src/client/conversation-viewer/conversation-viewer.vala 
b/src/client/conversation-viewer/conversation-viewer.vala
index ce7ae0f..ddcf8bc 100644
--- a/src/client/conversation-viewer/conversation-viewer.vala
+++ b/src/client/conversation-viewer/conversation-viewer.vala
@@ -852,7 +852,14 @@ public class ConversationViewer : Gtk.Box {
         string body_text = "";
         remote_images = false;
         try {
+            // get_body() recursively walks the MIME structure and serializes all text portions
+            // into a single string, converting to HTML in the process.  The inline image replacer
+            // is called for MIME parts that should be converted to HTML (i.e. for images not listed
+            // as attachments or as referenced elsewhere in the document by a Content-ID)
             body_text = message.get_body(true, inline_image_replacer) ?? "";
+            
+            // Next, convert the HTML into HTML suitable for our purposes, replacing references
+            // to images with data: URI's, noting when images refer to remote sources, and so forth
             body_text = insert_html_markup(body_text, message, out remote_images);
         } catch (Error err) {
             debug("Could not get message text. %s", err.message);