[MediaGalleries] Update overall package doc to include iphoto paragraph.

R=vandebo@chromium.org
BUG=343968

Review URL: https://codereview.chromium.org/215433003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@260273 0039d316-1c4b-4281-b951-d872f2087c98

chrome/common/extensions/docs/templates/intros/mediaGalleries.html

@@ -110,21 +110,42 @@ to read all the media files from galleries that the user selected.</p>
 
 <p>If present, the user's iTunes library can be accessed as a media gallery.
 In addition to the media files in the library, the "iTunes Music Library.xml"
-file is also presented. Regardless of where the music files are actually on the
-disk (and where the xml file says they are), they are mapping into an
-Artist/Album/Track hierarchy like iTunes does by default.  This mapping doesn't
-always work perfectly, so there are two things to note for Apps trying to match
-the xml file with files in the gallery. If the filenames for tracks within an
-album are not unique, they will be uniquified by adding the track id in
-parentheses before the extension, and if there is a colon or a slash in the
-artist, album, or track name, they are turned into underscore characters.</p>
+file is also presented.</p>
+<p>Regardless of where the music files are actually on the disk (and where
+the xml file says they are), they are mapped into an Artist/Album/Track
+hierarchy like iTunes does by default.  This mapping doesn't always work
+perfectly, so there are two things to note for Apps trying to match the
+xml file with files in the gallery.</p>
+<p>If the filenames for tracks within an album are not unique, they will be
+uniquified by adding the track id in parentheses before the extension, and
+if there is a colon or a slash in the artist, album, or track name, they are
+turned into underscore characters.</p>
 
 <h2 id="Picasa">Picasa</h2>
 
 <p>If present, the user's Picasa library can also be accessed as a media
 gallery. Directories on the filesystem scanned by Picasa are presented under
-folders/. Picasa Albums are presented under albums/. Albums and Folders that
-have duplicate names and dates will be uniquified using an incrementing
-integer in parenthesis before the extension. Duplicate filenames within the
-same Album will also be uniquified using an incrementing integer in parenthesis
-before the extension.</p>
+folders/. Picasa Albums are presented under albums/.</p>
+<p>Albums and Folders that have duplicate names and dates will be uniquified
+using an incrementing integer in parenthesis before the extension.</p>
+<p>Duplicate filenames within the same Album will also be uniquified using an
+incrementing integer in parenthesis before the extension.</p>
+
+<h2 id="iPhoto">iPhoto</h2>
+
+<p>If present, the user's iPhoto library can be accessed as a media gallery.
+The files are structured within a subdirectory called "Albums/". Within that
+subdirectory, each album in the user's iPhoto library will appear as a
+subdirectory by name, and contain file entries for the photos in that album.
+</p>
+<p>Duplicate album names or image filenames with albums will get a
+disambiguating suffix like "(NN)" where NN is a unique number.</p>
+<p>Any items appearing in multiple albums in iPhoto will appear in all those
+albums in the gallery.</p>
+<p>If the user has modified any images within an album, there will be an
+additional subdirectory called "originals/" within the album directory, which
+will then contain the original image, which will have the same filename as
+the file in the album itself. The file as it appears in the album directory,
+though, will be the one the user has invested time cropping, rotating, or
+otherwise editing.</p>
+