Fix code hover for bean-style reference to static import method

[eric-milles]

Consider the following:

package a
class B {
  static getX() {
  }
}

import static a.B.getX
x // hover or F2 this

Code hover (F2) on single-character, bean-style reference to static method getX fails to display information on the method. Code select (F3) works properly.

[eric-milles]

This is due to the GroovyTypeDeclaration created for the script, which shares the offset of the script body and has length 1.

[eric-milles]