The non-power-of-two extension available on OpenGL ES 2.0 is GL_OES_texture_npot. We should check for that extension as well as the desktop NPOT extension:

--- a/prism-es2/src/com/sun/prism/es2/GLContext.java Sun May 12 18:07:35 2013 +0300
+++ b/prism-es2/src/com/sun/prism/es2/GLContext.java Sun May 12 21:16:27 2013 +0300
@@ -252,7 +252,8 @@
              * GLContext class. */
             nonPowTwoExtAvailable = PrismSettings.forcePow2
                 ? Boolean.FALSE
- : ES2Pipeline.glFactory.isGLExtensionSupported("GL_ARB_texture_non_power_of_two");
+ : (ES2Pipeline.glFactory.isGLExtensionSupported("GL_ARB_texture_non_power_of_two")
+ || ES2Pipeline.glFactory.isGLExtensionSupported("GL_OES_texture_npot"));
         }
         return nonPowTwoExtAvailable.booleanValue();
     }

This gets us better rendering performance on the Pi.