Merge pull request #32307 from davidflanagan/bug1212226

Bug 1212226 - pass the correct EXIF preview metadata when creating a thumbnail r=aosmond

apps/camera/js/controllers/preview-gallery.js

@@ -404,22 +404,28 @@ PreviewGalleryController.prototype.onHidden = function() {
 };
 
 PreviewGalleryController.prototype.updateThumbnail = function() {
-  var self = this;
+  // This is the media item that we want to create a thumbnail for.
   var media = this.thumbnailItem = this.items[0] || null;
-  var blob;
 
   if (media === null) {
     this.app.emit('newthumbnail', null);
     return;
   }
 
-  if (media.isVideo) {
+  // To create a thumbanil, we first need to figure out which image
+  // blob to use, and what the size and rotation of that image is.
+  var blob;                    // The image we'll create the thumbnail from.
+  var metadata = {             // The metadata for that image.
+    rotation: media.rotation,
+    mirrored: media.mirrored
+  };
 
+  if (media.isVideo) {
     // If it is a video we can create a thumbnail from the poster image
     blob = media.poster.blob;
-    media = media.poster;
+    metadata.width = media.poster.width;
+    metadata.height = media.poster.height;
   } else {
-
     // If it is a photo we want to use the EXIF preview rather than
     // decoding the whole image if we can.
     if (media.preview) {
@@ -435,21 +441,23 @@ PreviewGalleryController.prototype.updateThumbnail = function() {
       if (Math.abs(fullRatio - previewRatio) < 0.01) {
         blob = media.blob.slice(media.preview.start, media.preview.end,
                                 'image/jpeg');
+        metadata.width = media.preview.width;
+        metadata.height = media.preview.height;
       }
     }
 
     // If a thumbnail couldn't be obtained from the EXIF preview,
     // use the full image
     if (!blob) {
       blob = media.blob;
+      metadata.width = media.width;
+      metadata.height = media.height;
     }
   }
 
-  createThumbnailImage(blob, media, this.thumbnailSize, gotThumbnail);
-
-  function gotThumbnail(blob) {
-    self.app.emit('newthumbnail', blob);
-  }
+  createThumbnailImage(blob, metadata, this.thumbnailSize, (thumbnail) => {
+    this.app.emit('newthumbnail', thumbnail);
+  });
 };
 
 });