You should major in whatever subject interests you. Had a blast in AP Art History in high school and want to major in it? Awesome, go for it. Contrary to popular belief, it is not necessary for pre-med students to major in biology. In fact, majoring in a subject other than biology may help you “stick out” as an applicant. That said, if you really love biology, you should major in it. Choosing a major should be about what interests you, not about about what “looks good”. Keep in mind, however, that even if you're not majoring in a science, you will still have to take a lot of science classes in order to be pre-med.
Most schools, including UC Berkeley, do not have a “pre-med” major. Instead, students interested in applying to medical school need to take various science classes, regardless of their major. Most medical schools require 2 semesters of general chemistry with lab, 2 semesters of organic chemistry with lab, 2 semesters of biology with lab, and 2 semesters of physics with lab. Additionally, many medical schools require a semester or two of math, as well as a semester or two of English. Some schools may even require additional science classes or humanities classes. It is important for you to start checking out the web sites of various medical schools to see what their requirements are. You don't want to be a second semester senior when realize you have to take another English class to apply to a med school you want to apply to.
Many students major in biology because a lot of the pre-med requirements overlap with the biology major requirements. But don't worry if none of your major requirements overlap with the pre-med requirements. I am in my final semester at Berkeley as a psychology major and I was able to get all of my major requirements and pre-med requirements done on time even though there was only 1 class that overlapped between the two.