To be protected under the whistleblower protection act, "Whistleblowers may file complaints that he or she reasonably believes evidences a violation of a law, rule or regulation; gross mismanagement; gross waste of funds; an abuse of authority; or a substantial and specific danger to public health or safety."
The complaints may be made internally (within the structure of the organization itself) or externally (media, watchgroups, etc)
However, the whistleblower act does NOT protect one from violations of national security and secrets.
As an example, it may be an abuse of power to send spies to Africa to see if one's spouse is cheating on them. However, that does not mean that releasing the names of the undercover spies is not treasonous - they may be re-assigned, but if their cover is blown they are suddenly useless as spies, possibly becoming targets, and our overall ability to carry out our security detail is weakened.
So there's a balance that has to be maintained between releasing enough information, to the right people, to stop the waste, fraud, and abuse, but not so much that it weakens our ability to carry out or national security needs or provide information to other countries that put us at a disadvantage.
The court case will hinge on whether the information truly showed areas of abuse/waste/fraud/illegal activity, and whether the informant released more information than was necessary to get the agency to change for the better, or released information that was too sensitive to release to the press, and puts the agency at a disadvantage.