canvas and textAlign: middle not recognized

[fredj]

http://openlayers.org/dev/examples/symbolizers-fill-stroke-graphic.html?renderer=Canvas

don't draw the labels because the textAlign value is "middle": this value is not recognized. Valid values are: start, end, left, right, or center.

See:  http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#dom-context-2d-textalign

[fredj]

The examples works with FF 3.0 but not with FF 3.5.6 and 3.6

[fredj]

change the textAlign default value from middle to center

[fredj]

The patch change the default value for textAlign.

Works with FF 3.0.17 and 3.6 (on linux).

Please review (and test with other canvas friendly browsers)

[bartvde]

(In [10113]) canvas and textAlign: middle not recognized, I made one change to original patch to not include the default value in LABEL_ALIGN since I did not see the purpose of adding that, p=fredj, r=me (closes #2439)

[bartvde]

Btw, fredj, sorry for taking your commit. I did not have enough coffee as yet apparantly.