In the end Phys.org decided to return to the original fraud:

http://phys.org/news/2015-09-precise...-constant.html
Phys.org: "Most precise test of Lorentz symmetry for the photon finds that the speed of light is indeed constant. (...) One important consequence of Lorentz symmetry is that the speed of light is invariant, or a constant in vacuum. The fact that photons in vacuum always move at a speed of just under 300,000 km per second is intimately connected to the concepts in special relativity. In the new study, the researchers performed an experiment that attempted to measure any tiny frequency variation of light, which would indicate a variation in the speed of light. Their experiment consists of a highly sensitive Michelson-Morley cavity test, which is an updated version of the seminal Michelson-Morley interferometer used in the late 1800s to measure the speed of light in the search for an "aether" that pervaded the universe (for which, of course, no evidence was found)."

Experiments of the Michelson-Morley type cannot prove that the speed of light is constant. Rather, they show the opposite. In 1887 (prior to FitzGerald and Lorentz advancing the ad hoc length contraction hypothesis), the Michelson-Morley experiment unequivocally confirmed the variable speed of light predicted by Newton's emission theory of light and refuted the constant (independent of the speed of the light source) speed of light predicted by the immobile ether theory and later adopted by Einstein as his special relativity's second postulate:

http://www.pitt.edu/~jdnorton/papers...nion_final.pdf
"These efforts were long misled by an exaggeration of the importance of one experiment, the Michelson-Morley experiment, even though Einstein later had trouble recalling if he even knew of the experiment prior to his 1905 paper. This one experiment, in isolation, has little force. Its null result happened to be fully compatible with Newton's own emission theory of light. Located in the context of late 19th century electrodynamics when ether-based, wave theories of light predominated, however, it presented a serious problem that exercised the greatest theoretician of the day."

http://philsci-archive.pitt.edu/1743/2/Norton.pdf
"In addition to his work as editor of the Einstein papers in finding source material, Stachel assembled the many small clues that reveal Einstein's serious consideration of an emission theory of light; and he gave us the crucial insight that Einstein regarded the Michelson-Morley experiment as evidence for the principle of relativity, whereas later writers almost universally use it as support for the light postulate of special relativity. Even today, this point needs emphasis. The Michelson-Morley experiment is fully compatible with an emission theory of light that CONTRADICTS THE LIGHT POSTULATE." x

http://books.google.com/books?id=JokgnS1JtmMC
Relativity and Its Roots, Banesh Hoffmann, p.92: "There are various remarks to be made about this second principle. For instance, if it is so obvious, how could it turn out to be part of a revolution - especially when the first principle is also a natural one? Moreover, if light consists of particles, as Einstein had suggested in his paper submitted just thirteen weeks before this one, the second principle seems absurd: A stone thrown from a speeding train can do far more damage than one thrown from a train at rest; the speed of the particle is not independent of the motion of the object emitting it. And if we take light to consist of particles and assume that these particles obey Newton's laws, they will conform to Newtonian relativity and thus automatically account for the null result of the Michelson-Morley experiment without recourse to contracting lengths, local time, or Lorentz transformations. Yet, as we have seen, Einstein resisted the temptation to account for the null result in terms of particles of light and simple, familiar Newtonian ideas, and introduced as his second postulate something that was more or less obvious when thought of in terms of waves in an ether. If it was so obvious, though, why did he need to state it as a principle? Because, having taken from the idea of light waves in the ether the one aspect that he needed, he declared early in his paper, to quote his own words, that "the introduction of a 'luminiferous ether' will prove to be superfluous."

Pentcho Valev