New tests for component aliasing with duplicated inputs which match
the same output variable in the previous stage.

From Section 4.4.1 (Input Layout Qualifiers) of the GLSL 4.60 spec:

  " Location aliasing is causing two variables or block members to
    have the same location number. Component aliasing is assigning the
    same (or overlapping) component numbers for two location
    aliases. (Recall if component is not used, components are assigned
    starting with 0.) With one exception, location aliasing is allowed
    only if it does not cause component aliasing; it is a compile-time
    or link-time error to cause component aliasing."

From Section 7.4.1 (Shader Interface Matching) of the OpenGL 4.60 spec:

  "   * An output variable is considered to match an input variable in
        the subsequent shader if:

        – the two variables match in name, type, and qualification,
          and neither has a location qualifier, or

        – the two variables are declared with the same location and
          component layout qualifiers and match in type and
          qualification."

Cc: Timothy Arceri <tarceri@itsqueeze.com>
Cc: Iago Toral Quiroga <itoral@igalia.com>
Cc: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Andres Gomez <agomez@igalia.com>
Reviewed-by: Juan A. Suarez <jasuarez@igalia.com>