Bug 873721: Remove positioning code for reflow-on-zoom when pinch-zooming to provide a better user experience.[r=kats]
Now that double-tap reflow-on-zoom has landed, we need to be a bit more careful about how the position maintenance code for reflow-on-zoom happens and which events trigger it. This patch removes the code that previously did position maintenence for reflow-on-zoom during a pinch-zoom event, but adds back the onPinchFinish() handler so that when pinch-zooming out, we can reset the max line box width if it changed due to a double-tap zoom event previously encountered.
Bug 875929 - Now that js_bitscan_ctz64 and js_bitscan_clz64 are implemented on all platforms, clean up some compatibility code which isn't needed anymore. r=evilpies