After significantly overhauling Windows last year, we knew that Microsoft was committed to its new mobile strategy, even in the face of disappointing sales of its first generation of Surface tablet devices. What remained unclear, however, was whether the Redmond giant would venture into the crowded 7-inch tablet market, which now contains products from Apple, Amazon, Google, Samsung, and many others. According to a report late Wednesday from The Wall Street Journal, that’s exactly what Microsoft plans to do. The…