This is true for draw and impress.
The alignment-icon shows "align left" no matter what the actual funcion is. The
last choice is remembered and applied, but not shown on the toolbar.

Steps to reproduce:
0) Open a new draw/impress document and insert a rectangle
1) Select the rectangle and click on the alignment-icon

-> rectangle will be left-aligned relative to the page (as expected)

2) Click on the drop-down arrow on the alignment-icon and choose "align to top"

-> rectangle now will be placed at the top-left corner of the page (as 
   expected), the icon still shows "align left"

3) Drag the rectangle to the center of the page
4) Click on the alignment-icon

-> The rectangle will be moved to the top of the page, although the icon shows
"align left" (expected behaviour: move to the left)

Fix: 
Replace the icon by the alignment last applied (and apply the alignment shown on
the icon on subsequent clicks on the icon) -> prefered solution

Always show "align left" and always align left when icon is clicked (for
different alignments, user has to choose from the drop-down) -> should only be
last resort. Undesireable but better than current behaviour (icon and function
don't match).