Hi,

When in GD environment, adding a watermark to the image doesn't work.
The problem happens when we save & close the image.
In the preview, the image is without watermark.

Note:

• Works fine on Image Magik

  Steps to reproduce

  Use the following filter for this Test Case:
  --filter="eZWebinAdminSeleneseTests.*with_ezie.html"
  

  Setup
  
  This test must be done twice. One for  ImageMagick and other for GD
  By default, ImageMagick is enable.
  1: To disable ImageMagik (enabling GD), each time the filter is executed, the following actions must be done
      vi .run/settings/override/image.ini.append.php
      Add or change the following line:
      [ImageMagick]
      IsEnabled=false
  
  Create an image object
  
     1. Log in as admin on eZFlow
     2. Create a new folder named "Create Images"
     3. Click on "Create Images" link on top menu
     4. Select "Image" in the content class dropdown list
     5. Click on "Create here" button
     6. Fill in the image details:
            * Title: "TC-282"
            * Summary: Test Case
            * Image: browse for a file, and select the "Jellyfish.jpg" image attached to the "eZ Image Editor" test suite
     7. Click on "Store draft"
  
  Launch the image editor
  
     1. Click on the "Edit" button below the image
     2. Check that the image editor interface shows up, with the "Actions" toolbar and the "eZ Image Editor" floating window.
     3. Click on the "Fit on screen" button to display the full image
  
  Check that the Watermark interface is complete
  
     1. Click on "Watermark" in the left toolbar
     2. Verify that the right toolbar now contains the "Watermarks" block
     3. Select the "Ez" watermark
     4. Click on the first icon in the 9 icons described at step 3 (top left)
     5. Check that the overlay has been moved to the top left corner of the image
     6. Verify that a selection rectangle appears around the watermark, with size handlers (the 9 litle squares in the selection rectangle)
     7. Left-click the mouse button on the right-botton size handler on the selection (leaving the mouse button down) and drag the mouse to the left
     8. Verify that the watermark diminish size.
     9. Unpress the left-mouse button
    10. Left-click the mouse button on the right-botton size handler on the selection (leaving the mouse button down) and drag the mouse to the right
    11. Verify that the watermark raises size.
    12. Unpress the left-mouse button when the watermark has more or less the double of the original size
    13. Click on "Apply"
    14. Check that the overlay (watermark) has been added to the image with expected size (more or ess the double of original size).
  
  Save the image and check if it has been edited and with watermark size changed
  
     1. Click on "Save & Close"
     2. Check that the image editor interface closes
     3. Check that the image in the preview column contains the watermark