Don't re-allocate buffers used by Visualizer callbacks as this causes an unacceptable amount of GC thrash. Instead, lazily allocate the buffers and only reallocate them when the required size changes. See http://b/issue?id=5717519 for details. Change-Id: I50458961992a64d9b3c46db7e5e8e6414a92228f Signed-off-by: John Grossman <johngro@google.com>