an uninitialized variable caused the unmapping of some random pages
when buffers were resized, which happens on orientation changes.
unfortunatelly, I'm still seeing crashes on orientation changes, but
less of them and less random ones. so far, I've only seen an ASSERT
triggering in the GL driver, all "meomry corruptions" (crashes in
dalvik, skia, etc...) seem gone.
Change-Id: Icd6077e26e050670b75b715f205b6c7c9ea1a476