...that information would have been protected as a trade secret, but it lost its protection because Apple was careless giving the phone to an employee who lost it.
Gizmodo could have created their blog without buying the iPhone, by leaving the phone with the person who found it and examining it while it was in the guy's possession. And they would have paid good money for that. The information about the phone was fair game once the trade secret was lost.
Gizmodo took the phone and the information. The phone was protected by all the usual property rights. The information was not protected, because the trade secret protection was lost.
I certainly don't believe that Apple was careless in entrusting its test phone to an employee, but even accepting your assertion, I don't believe that Gizmodo would have been permitted to disclose Apple's trade secrets it learned from examining the phone with the connivance of the finder. Since the finder was himself a thief, he had no power to give any "permission" or to bestow any rights at all on Gizmodo. Gizmodo had no right to do anything with respect to the phone that was inconsistent with the rights of the true owner. Taking apart someone else's phone, I think most people would agree, is such an inconsistent act.
The California version of the Uniform Trade Secrets Act provides in pertinent part:
(b) "Misappropriation" means:
(1) Acquisition of a trade secret of another by a person who knows or has reason to know that the trade secret was acquired by improper means; or
(2) Disclosure or use of a trade secret of another without express or implied consent by a person who:
(A) Used improper means to acquire knowledge of the trade secret; or
(B) At the time of disclosure or use, knew or had reason to know that his or her knowledge of the trade secret was:
(i) Derived from or through a person who had utilized improper means to acquire
it...
"Improper means" includes the commission of a tort against property rights. Trespassing on Apple's headquarters is no more an improper means to acquire trade secrets than trespassing against the chattel, the test iPhone.
So I think that even had Gizmodo examined the phone while the finder continued to exercise primary control of it, Gizmodo still would be guilty of misappropriation of the trade secrets it learned through tortious conduct.
I'll leave it to the IP experts to comment on the extent to which trade secrets discovered in the course of a good faith attempt to identify the owner of lost property may be disclosed. Gizmodo's claim, however disingenuous, that it had to take apart the phone to find the identity of the owner to whom it fervently wished to return it was connected with its interpretation of the California USTA in this regard.